A scrum (short for scrummage) is a method of restarting play in rugby that involves players packing closely together with their heads down and attempting to gain possession of the ball.  Depending on whether it is in rugby union or rugby league, the scrum is utilized either after an accidental infringement or when the ball has gone out of play. Scrums occur more often, and are now of greater importance, in union than in league.  Starting play from the line of scrimmage in gridiron football is derived from the scrum.
In both sports, a scrum is formed by the players who are designated forwards binding together in three rows. The scrum then ‘engages’ with the opposition team so that the players’ heads are interlocked with those of the other side’s front row. In rugby union the initiation of the process is verbally coordinated by the referee who calls ‘crouch, bind, set’ as of 2013 (formerly ‘crouch, touch, pause, engage’, ‘crouch and hold, engage’ before 2007). The scrum-half from the team that did not infringe then throws the ball into the tunnel created in the space between the two sets of front rowers’ legs. Both teams may then try to compete for the ball by trying to hook the ball backwards with their feet.
A key difference between the two sports is that in rugby union both sets of forwards try to push the opposition backwards whilst competing for the ball and thus the team that did not throw the ball into the scrum have some minimal chance of winning the possession. In practice, however, the team with the ‘put-in’ usually keeps possession (92% of the time with the feed) and put-ins are not straight. Forwards in rugby league do not usually push in the scrum, scrum-halves often feed the ball directly under the legs of their own front row rather than into the tunnel, and the team with the put-in usually retains possession (thereby making the 40/20 rule workable).
A rugby union scrum consists of two teams’ eight forwards, with each team binding in three rows. The front row is composed of the two props and the hooker.  The two second row forwards (jersey numbers four and five), commonly referred to as the locks bind together and directly behind the front row with each putting their heads between the props and the hooker. Lastly the back row is made up of the two flankers and the number eight. The flankers bind on each side of the scrum — next to a lock and behind a prop. 
The two forward packs form a scrum by approaching to within an arms length of each other. The referee gives the command crouch and the opposing front rows then crouch. Then the referee calls touch and props touch the opposites outside shoulder. The referee then issues the set command which indicates that the two packs may come together. When this happens both front rows thrust forward with the tighthead props’ heads going between the opposing hooker and loosehead prop. The props then bind by gripping the back or side of the opposing prop’s jersey. The scrum-half from the team that has possession then throws the ball in the gap formed between the two front rows.  The two hookers (and sometimes the props) then compete for possession by trying to hook the ball backwards with their feet, while the entire pack tries to push the opposing pack backwards. The side that wins possession usually transfers the ball to the back of the scrum — which is done with their feet. Once at the back it is picked up either by the number 8, or by the scrum-half. 
Starting with the 2012/2013 rugby season the International Rugby Board has issued trial law amendments, one of which affects the call sequence. The referee will continue to start with «crouch» and «touch», but will now issue the command «set», which replaces «engage» as the indication that the packs may push forward. «Pause» has been removed in order to speed up the scrum and to minimize resets due to collapsed scrums.  The command to «touch» was not used before 2007. Instead, the referee called «crouch and hold», at which time each pack crouched and held that position before the referee gave the command to «engage». Starting in 2013/2014 «touch» has been replaced with «bind».
There are a large number of rules regarding the specifics of what can and cannot be done during a scrum. Front rowers must engage square on, rather than bore in on an angle.  Front-rowers are also banned from twisting their bodies, pulling opponents, or doing anything that might collapse the scrum.  The back row must remain bound until the ball has left the scrum. For flankers, this means keeping one arm, up to the shoulder, in contact with the scrum. The scrum must be stable, stationary and parallel to the goal-lines when they feed the ball; otherwise a free kick is awarded to the non-offending team. By strict letter of the law, the ball must be fed into the middle of the tunnel with its major axis parallel to the ground and touchline; however this is becoming less strictly enforced as the photo in this article illustrates. The ball must be thrown in quickly and in a single movement — this means that a feed cannot be faked. Once the ball has left the hands of the scrum-half the scrum has begun.
Rugby sevens Edit
Scrums in rugby union sevens consist only of what would be the «front row» in normal rugby union. They consist of three forwards on each side, plus a scrum half to feed in the ball.
A rugby league scrum is used to bring the ball back into play in situations where the ball has gone out of play over the touchline or a player has made a mistake, a knock-on or forward pass, except when that mistake has occurred on the last tackle of a set of six tackles. A scrum is also used in the rare event that the ball bursts or the referee interferes with the movement of the ball.
The scrum consists of six players from each team in a 3-2-1 formation. The scrum is usually formed by each team’s forwards, though any player can participate. The front row of the formation consists of the open-side prop (8), hooker (9) and blind-side prop (10). Behind the front row are the two second row forwards (11&12), and then the loose forward (13) at the back.
The two «packs» of forwards form a scrum before the ball is put into the scrum. The scrum-half (7) (also known as the halfback) of the team that did not commit the forward pass, knock-on or cause the ball to go out of play over the touch line puts the ball into the scrum through the tunnel formed by the front rows of each set of forwards meeting. When the ball bursts or the referee interferes with the ball, the team that had possession at the time is the one to put the ball into the scrum. Both teams may attempt to secure the ball while it is in the scrum by «hooking» for it or by pushing their opponents off the ball. The ball can be brought back into open play by the scrum-half retrieving it from the rear of the scrum or by the loose forward picking it up after detaching from the scrum. 
While restarting play, the scrum serves to keep the forwards in one area of the field for a time, thus creating more space for back play and special plays, an advantage to the side that wins the scrum. It is now uncommon for the team not awarded the scrum feed to win possession «against the feed». Prior to 1983, the loose forward would often stand outside of the scrum, leaving a five-man scrum. In an effort to provide more space for backline play, scrum rules were changed so that in normal circumstances loose forwards must always bind into the scrum. However, if a player is sent off, five-man scrums may occur. In this situation, the rules mandate the numbers of players not bound into the scrum. 
While the Laws of the Game continue to provide for competitive scrums,   a convention exists that some scrum rules are not enforced. During the 1970s, scrum penalties for feeding the ball into the legs of the second row, packs moving off the «mark» or collapsing the scrum were seen as unattractive. The ability of teams to win a game purely on goals from scrum penalties was also seen as unfair. In an effort to improve this situation, changes to rules and their enforcement were made. The number of scrums was reduced with the introduction of the «handover» after a team has used a set of six tackles,  the differential penalty, one which cannot be kicked at goal was brought in for offences at scrums and referees ceased enforcing some rules regarding feeding the ball into scrum. Aided by this change, it is common for professional teams not to fully contest scrums, according to their choice of tactics.
An agile team in a Scrum environment often still includes people with traditional software engineering titles such as programmer, designer, tester, or architect.
But on a Scrum team, everyone on the project works together to complete the set of work they have collectively committed to complete within a sprint, regardless of their official title or preferred job tasks.
Because of this, Scrum teams develop a deep form of camaraderie and a feeling that «we’re all in this together.»
When becoming a Scrum team member, those who in the past fulfilled specific traditional roles tend to retain some of the aspects of their prior role but also add new traits and skills as well. New roles in a Scrum team are the ScrumMaster or product owner.
A typical Scrum team is three to nine people. Rather than scaling by having a large team, Scrum projects scale through having teams of teams. Scrum has been used on projects with over 1,000 people. A natural consideration should, of course, be whether you can get by with fewer people.
Although it’s not the only thing necessary to scale Scrum, one well-known technique is the use of a «Scrum of Scrums» meeting. With this approach, each Scrum team proceeds as normal, but each team identifies one person who attends the Scrum of Scrums meeting to coordinate the work of multiple Scrum teams.
These meetings are analogous to the daily Scrum meeting, but do not necessarily happen every day. In many organizations, having a Scrum of Scrums meeting twice a week is sufficient.
The illustration below shows how a Scrum of Scrums facilitates cross-team coordination. Each circle represents one person on a Scrum team. The bottom row of this illustration shows teams with eight or nine members on each. One person from each team (the shaded circle) also participates in a Scrum of Scrum to coordinate work above that team. Those teams further coordinate their work with a Scrum of Scrum of Scrums.
Scrum Foundations Video Series
All the foundational knowledge of Scrum including: the framework, values, different roles, meetings, backlogs, and improving efficiency & quality.
The Scrum approach to agile software development marks a dramatic departure from waterfall management. Scrum and other agile methods were inspired by its shortcomings. Scrum emphasizes collaboration, functioning software, team self management, and the flexibility to adapt to emerging business realities.
The Scrum Team Role
Posted by admin under Scrum Basics
There are three roles in the Scrum method of software development: the Product Owner, the ScrumMaster, and the team.
A Scrum team includes seven members, plus or minus two. Scrum teams are cross-functional, including the skills (but ideally not the job titles) of software engineers, architects, programmers, analysts, QA experts, testers, UI designers, etc. It is recommended all team members be located in a team room, and collaborate more intensely than a traditional team. They avoid handoffs and phases. The ScrumMaster encourages the team to learn modern development practices such as Test Driven Development (TDD).
While the development team wants to complete the work negotiated in the Sprint Planning Meeting, the team has complete control over the amount of work it takes on. The Product Owner ensures the team takes on the highest priority work.
The team has the autonomy to determine how and when to complete its work. It’s not unusual for teams to discover within the first few days of a sprint, as analysis becomes less fuzzy, that it has more work to do than it realized at the start. A project’s finishing touches are often the most time-consuming and labor-intensive.
Teams are responsible to inspect and adapt their process in the Sprint Retrospective Meeting.
In Large Scale Scrum, teams are responsible for their co-ordination with the world outside them, including other teams. Scrum does not use traditional co-ordination roles such as project manager and PMO.
Here is what Scrum looks like from a developer’s perspective:
- Sama Zahid | April 4th, 2011 at 8:08 am
I have recently started working and readin gabout SCRUM framework and your blog does provider the neccessary in short and well explaines manner. It’s a must for SCRUM newcomers.
Scrum Roles — The Scrum Team
Within the Scrum Framework three roles are defined:
- The Scrum Team
- Scrum Master
- Scrum Product Owner
Each of these roles has a defined set of responsibilities and only if they fulfill these responsibilities, closely interact and work together they can finish a project successfully.
Scrum Roles & Stakeholders
The Scrum Team
Within the Scrum Framework all work delivered to the customer is done by dedicated Scrum Teams. A Scrum Team is a collection of individuals working together to deliver the requested and committed product increments.
To work effectively it is important for a Scrum Team that everyone within the team
- follows a common goal
- adheres the same norms and rules
- shows respect to each other
When setting up a new Scrum Team one always has to keep in mind that no new team will deliver with the highest possible performance right from the beginning. After setting up the team it has to go through certain phases as described by the Tuckman-Model: Forming, Storming, Norming, Performing.
How long it takes until the Scrum Team is in the Performing Phase depends on the team, and yet it normally takes about 3 Sprints until the teams is mature enough to deliver their results in a predictable way.
Characteristics of a Scrum Team
Scrum Teams always have the following characteristics:
- Team members share the same norms and rules
- The Scrum team as a whole is accountable for the delivery
- The Scrum Team is empowered
- It is working as autonomous as it is possible
- The Scrum Team is self organizing
- The skills within the Scrum team are balanced
- A Scrum Team is small and has no sub-teams
- The people within the Scrum Team work full time in the team
- People are collocated
Rules & Norms
Of course their environment defines some of the norms the teams have to follow, but some rules and norms are developed during the Norming phase. This set of common rules is quite important. Otherwise the team members would have to constantly waste valuable time to switch between different value systems and rule sets. Examples for such norms and rules are:
- time and location of the Daily Scrum Meeting
- the Definition Of Done (DoD) used to decide if work is finished or not
- coding guidelines
- tools to use
The Scrum Team as a whole is responsible to deliver the committed delivery in time and with the defined quality. A good result or a failure is never attributed to a single team member but always the result of the Scrum Team.
Empowerment & Self organization
The Scrum Team has to be empowered to define
- what it will commit to deliver at the end of the sprint
- how the expected results have to be broken down into tasks
- who will perform the task and in which order they are performed
Only if the Scrum Team is empowered to decide these things it will work with the highest possible motivation and performance.
Balanced set of skill
Individuals within the Scrum Team will most certainly have specialized skills and focus. However to achieve best possible performance it would be optimal to have a balanced set of skills. Only then the Scrum Team will be able to deal with the ever-changing challenges and can act as autonomous as it is possible.
On one hand this means that a Scrum Team should be multidisciplinary (developers, tester, architects etc) right from the beginning. On the other hand this also means that each team member should learn a little bit of each other’s specialization, e.g. a if required to finally reach the committed goal a developer should also perform or write tests.
As a consequence this also means that within the Scrum Framework it is not differentiated between e.g. «tester» and «architect», they all share the same title «Scrum Team Member» even if the primary skill is not to develop production code.
Size of the Scrum Team
Scrum Teams are small. The ideal size is 7 +/- 2 people.
If there are more people the communication overhead gets too large and the team should be split into multiple Scrum Teams. These Scrum Teams should be coordinated and communicate with each other but otherwise work independently.
To minimize unnecessary communication overhead each Scrum Team should be collocated. If work has to be spread over multiple locations, independent Scrum Teams should be created.
Responsibilities of the Scrum Team
The Scrum Team and each of the team members has certain responsibilities which have to be fulfilled:
- They have to breakdown the requirements, create task, estimate and distribute them. In other words this means that they have to create the Sprint Backlog.
- They have to perform the short Daily Sprint Meeting.
- They have to ensure that at the end of the Sprint potentially shippable functionality is delivered.
- They have to update the status and the remaining efforts for their tasks to allow creation of a Sprint Burndown Diagram.
A brief look into using the scrum framework for software development
Scrum is one of the most popular frameworks for implementing agile. So popular, in fact, that many people think scrum and agile are the same thing. (They’re not.) Many frameworks can be used to implement agile, such as kanban for example, but scrum has a unique flavor because of the commitment to short iterations of work.
A sprint is a short, time boxed period when a scrum team works to complete a set amount of work.
Sprint Planning is an event in scrum that defines what can be delivered in the upcoming sprint and how that work will be achieved.
Four agile ceremonies, demystified
Learn how to facilitate great agile ceremonies like sprint planning, daily stand-ups, iteration review and retrospectives.
The product backlog: your ultimate to-do list
What is a product backlog in agile or scrum? Learn about the best practices for managing and prioritizing a healthy product backlog.
Three steps to better sprint reviews
Learn how sprint reviews demonstrate the hard work of the entire team: designers, developers, and the product owner.
Standups for agile teams
Learn how standups contribute to a healthy agile program and some tips and tricks for you and your team.
What is a Scrum Master?
Learn what a Scrum Master is (and what they are NOT), and how the role supports and works with other members of an agile team.
Agile retrospectives: Use the past to define the future
A retrospective helps teams perform better over time. See what the agile community is saying and learn how to run your own retrospective meetings.
Learn scrum with Jira Software
A step-by-step guide on how to drive a scrum project, prioritize and organize your backlog into sprints, run the scrum ceremonies and more, all in Jira.
What’s so special about scrum?
With scrum, the product is built in a series of fixed-length iterations called sprints that give teams a framework for shipping software on a regular cadence. Milestones–i.e., the end of a sprint–come frequently, bringing with them a feeling of tangible progress with each cycle that focuses and energizes everyone. («Continuous inspiration» for the win!) Short iterations also reinforce the importance of good estimation and fast feedback from tests–both recurring struggles in waterfall projects.
Scrum calls for four ceremonies that bring structure to each sprint:
- Sprint planning: A team planning meeting that determines what to complete in the coming sprint.
- Daily stand-up: Also known as a daily scrum, a 15-minute mini-meeting for the software team to sync.
- Sprint demo: A sharing meeting where the team shows what they’ve shipped in that sprint.
- Sprint retrospective: A review of what did and didn’t go well with actions to make the next sprint better.
During a sprint, visual artifacts like task boards and burndown charts, visible to the team and spectators alike, are powerful motivators. They drive a spirit of «we’re doing this!» Having the opportunity to show off new work at the sprint demo is equally motivating, and the consistent, incremental feedback the team gets from stakeholders at each demo creates a powerful way to develop products.
Scrum done well–which is to say, not «waterfall with stand-ups»–can be a massive catalyst for improving team productivity and morale, and the product development process as a whole.
Three essential roles for scrum success
A scrum team has a slightly different composition than a traditional waterfall project, with three specific roles: product owner, scrum master, and the development team. And because scrum teams are cross-functional, «the development team» includes testers, designers, and ops engineers in addition to developers.
The product owner
Product owners are the champions for their product. They are focused on understanding business and market requirements, then prioritizing the work to be done by the engineering team accordingly. Effective product owners:
- Build and manage the product backlog
- Closely partner with the business and the team to ensure everyone understands the work items in the product backlog
- Give the team clear guidance on which features to deliver next
- Decide when to ship the product with the predisposition towards more frequent delivery
Keep in mind that a product owner is not a project manager. Product owners are not managing the status of the program. They focus on ensuring the development team delivers the most value to the business. Also, it’s important that the product owner be an individual. No development team wants mixed guidance from multiple product owners.
The scrum master
Scrum masters are the champion for scrum within their team. They coach the team, the product owner, and the business on the scrum process and look for ways to fine-tune their practice of it. An effective scrum master deeply understands the work being done by the team and can help the team optimize their delivery flow. As the facilitator-in-chief, they schedule the needed resources (both human and logistical) for sprint planning, stand-up, sprint review, and the sprint retrospective.
Scrum masters also look to resolve impediments and distractions for the development team, insulating them from external disruptions whenever possible.
Part of the scrum master’s job is to defend against an anti-pattern common among teams new to scrum: changing the sprint’s scope after it has already begun. Product owners will sometimes ask, «Can’t we get this one more super-important little thing into this sprint?» But keeping scope air tight reinforces good estimation and product planning–not to mention fends off a source of disruption to the development team.
Scrum masters are commonly mistaken for project managers, when in fact, project managers don’t really have a place in the scrum methodology. A scrum team controls its own destiny and self-organizes around their work. Agile teams use pull models where the team pulls a certain amount of work off the backlog and commits to completing it that sprint, which is very effective in maintaining quality and ensuring optimum performance of the team over the long-term. Neither scrum masters nor project managers nor product owners push work to the team (which, by contrast, tends to erode both quality and morale).
The scrum team
Strong scrum teams approach their project with a strong «we» attitude.
Scrum teams are the champions for sustainable development practices. The most effective scrum teams are tight-knit, co-located, and usually 5 to 7 members. Team members have differing skill sets, and cross-train each other so no one person becomes a bottleneck in the delivery of work. All members of the team help one another to ensure a successful sprint completion.
As mentioned above, the scrum team drives the plan for each sprint. They forecast how much work they believe they can complete over the iteration using their historical velocity as a guide. Keeping the iteration length fixed gives the development team important feedback on their estimation and delivery process, which in turn makes their forecasts increasingly accurate over time.
But wait: there’s more
Ok: so now you’ve been briefed. But understanding the philosophy of scrum and who is on a scrum team is only half of the equation. Keep reading to learn how scrum team members work together using common agile ceremonies as well as how the team in an agile program delivers work back to the business.
Agile has had a huge impact on me both professionally and personally as I’ve learned the best experiences are agile, both in code and in life. You’ll often find me at the intersection of technology, photography, and motorcycling. Find me on Twitter! @danradigan