At IBM Rational we define disciplined agile delivery as:
Disciplined agile delivery is an evolutionary (iterative and incremental) approach which regularly produces high quality solutions in a cost effective and timely manner via a risk and value driven life cycle. It is performed in a highly collaborative, disciplined, and self-organizing manner within an appropriate governance framework, with active stakeholder participation to ensure that the team understands and addresses the changing needs of its stakeholders to maximize business value provided. Disciplined agile delivery teams provide repeatable results by adopting just the right amount of ceremony for the situation which they face.
Let’s explore the key points in this definition:
- Full delivery life cycle. Disciplined agile delivery processes have life cycles which are serial in the large and iterative in the small. Minimally they have a release rhythm which recognizes the need for start up/inception activities, construction activities, and deployment/transition activities. Better yet, they include explicit phases as well. It is very important to note that these are not the traditional waterfall phases – requirements, analysis, design, and so on – but instead different “seasons” of a project. The point is that we need to look beyond agile software development and consider the full complexities of solution delivery. Adopting a full delivery life cycle, not just a construction life cycle, is arguably the “zeroth” agile scaling factor.
- Evolutionary. Agile strategies are both iterative and incremental in nature. Iterative means that you are working in a non-serial manner, on any given day you may do some requirements analysis, some testing, some programming, some design, some more testing, and so on. Incremental means that you add new functionality and working code to the most recent build, until such time as the stakeholder determines there is enough value to release the product.
- Regularly produces high quality solutions. Agilists are said to be quality focused. They prefer to test often and early, and the more disciplined ones even take a test-first approach where they will write a single test and the just enough production code to fulfill that test (then they iterate). Many agile developers have adopted the practice of refactoring, which is a technique where you make simple changes to your code or schema which improves its quality without changing its semantics. Adoption of these sorts of quality techniques seems to work – it appears that agile teams are more likely to deliver high quality systems than traditional teams (according to the DDJ 2008 Project Success survey). Within IBM we take it one step further and focus on consumability, which encompasses quality and other features such as ease of deployment and system performance. Furthermore, although some agile methods promote the concept of producing “potentially shippable software” on a regular basis, disciplined agile delivery teams produce solutions: a portion of which may be software, a portion of which may be hardware, and a portion of which will be the manner in which the system is used.
- Cost effective and timely manner. Agile teams prefer to implement functionality in priority order [http://www.agilemodeling.com/essays/prioritizedRequirements.htm], with the priority being defined by their stakeholders (or a representative thereof). Working in priority order enables agile teams to maximize the return on investment (ROI) because they are working on the high-value functionality as defined by their stakeholders, thereby increasing cost effectiveness. Agile teams also prefer to produce potentially shippable solutions each iteration (an iteration is a time-box, typically 2-4 weeks in length), enabling their stakeholders to determine when they wish to have a release delivered to them and thereby improving timeliness. Short iterations reduce the feedback cycle, improving the chance that agile teams will discover problems early (they “fail fast”) and thereby enable them to address the problems when they’re still reasonably inexpensive to do so. The DDJ 2008 Project Success survey found that agile teams are in fact more likely to deliver good ROI than traditional teams and more likely to deliver in a timely manner.
- Value driven life cycle. One result of building a potentially shippable solution every iteration is that agile teams produce concrete value in a consistent and visible manner throughout the life cycle.
- Risk and value driven life cycle. Core agile processes are very clear about the need to produce visible value in the form of working software on a regular basis throughout the life cycle. Disciplined agile delivery processes take it one step further and actively mitigate risk early in the life cycle – during project start up you should come to stakeholder concurrence regarding the project’s scope, thereby reducing significant business risk, and prove the architecture by building a working skeleton of your system, thereby significantly reducing technical risk. They also help with transition to agile, allowing traditional funding models to use these milestones before moving to the finer grained iteration based funding that agile allows.
- Highly collaborative. People build systems, and the primary determinant of success on a development project is the individuals and the way that they work together. Agile teams strive to work closely together and effectively as possible. This is a characteristic that applies to both engineers on the team, as well as their leadership.
- Disciplined. Agile software development requires greater discipline on the part of practitioners that what is typically required by traditional approaches.
- Self organizing. This means that the people who do the work also plan and estimate the work.
- Self-organization within an appropriate governance framework. Self-organization leads to more realistic plans and estimates which are more acceptable to the people implementing them. At the same time these self-organizing teams must work within an appropriate governance framework which reflects the needs of their overall organizational environment. An “appropriate governance framework” explicitly enables disciplined agile delivery teams to effectively leverage a common infrastructure, to follow organizational conventions, and to work towards organizational goals. The point is that project teams, regardless of the delivery paradigm they are following, need to work within the governance framework of their organization. More importantly, effective governance programs should make it desirable to do so. Our experience is that traditional, command-and-control approaches to governance where senior management explicitly tells teams what to do and how to do it don’t work very well with agile delivery teams. We’ve also found that lean development governance, an approach which is based on collaboration and enablement, is far more effective in practice. Good governance increases the chance that agile delivery teams will build systems which fit into your overall organizational environment, instead of yet another stand-alone system which increases your overall maintenance burden and data quality problems.
- Active stakeholder participation. Agile teams work closely with their stakeholders, who include end users, managers of end users, the people paying for the project, enterprise architects, support staff, operations stuff, and many more. Within IBM we distinguish between four categories of stakeholder: principles/sponsors, partners (business partners and others), end users, and insiders These stakeholders, or their representatives (product owners in Scrum, or on-site customers in Extreme Programming, or a resident stakeholder in scaling situations), are expected to provide information and make decisions in a timely manner.
- Changing needs of stakeholders. As a project progresses your stakeholders will gain a better understanding of what they want, particularly if you’re showing them working software on a regular basis, and will change their “requirements” as a result. Changes in the business environment, or changes in organization priority, will also motivate changes to the requirements. There is a clear need for agile requirements change management [http://www.agilemodeling.com/essays/changeManagement.htm] on modern IT projects.
- Repeatable results. Stakeholders are rarely interested in how you delivered a solution but instead in what you delivered. In particular, they are often interested in having a solution which meets their actual needs, in spending their money wisely, in a high-quality solution, and in something which is delivered in a timely manner. In other words, they’re interested in repeatable results, not repeatable processes.
- Right amount of ceremony for the situation. Agile approaches minimize ceremony in favor of delivering concrete value in the form of working software, but that doesn’t mean they do away with ceremony completely. Agile teams will still hold reviews, when it makes sense to do so. DDJ’s 2008 Modeling and Documentation Survey found that agile teams will still produce deliverable documentation, such as operations manuals and user manuals, and furthermore are just as likely to do so as traditional teams. The DDJ September 2009 State of the IT Union survey found that the quality of the documentation delivered by agile teams was just as good as that delivered by traditional teams, although iterative teams (e.g. RUP teams) did better than both agile and traditional.
There is a fair bit of rhetoric surrounding agile methods, some of which we subscribe to and some of which we don’t. We’d like to briefly examine the rhetoric which we’ve found to be the most misleading for people trying to be effective at adopting agile techniques. The following list is in the format X but Y, where X is the rhetoric and Y is the strategy promoted by the Disciplined Agile Delivery (DAD) process framework. This includes:
- Requirements evolve throughout the lifecycle BUT the scope should still be agreed to at the beginning of the project. There has to be an initial vision for a project, a vision which your stakeholders should help define and then agree to, and to come to that vision you will need to perform some initial requirements envisioning. A list of high level features is part of this initial vision. Yes, the details are very likely to evolve over time but the fundamental goals of your project and scope of your effort needs to be defined early in your project. In a very small minority of situations you may not be able to get the right people together, either physically or virtually, to define the initial vision – this should be seen as a significant project risk.
- Simple designs are best BUT the architecture should be thought out early in the lifecycle. Too many developers interpret the advice to focus on simple designs to mean that they should build everything from scratch. Yet more often than not the simplest design is to take advantage of what is already there, and the best way to do that is to work closely with people who understand your existing technical infrastructure. Investing in a little bit of architectural envisioning early in the lifecycle enables your team to identify existing enterprise assets that you can leverage, to identify your architectural options, and to select what appears to be the best option available to you. The details will still emerge over time, and some decisions will be deferred until a later date when it’s more appropriate to make them, but the bottom line is that disciplined agilists think before they act.
- Teams should be self organizing BUT they are still constrained (and enhanced) by your organizational ecosystem. Intellectual workers, including IT professionals, are most effective when they have a say in what work they do and how they do it. IT professionals can improve their productivity by following common conventions, leveraging and building out a common “dev-ops” infrastructure, building towards a common vision, and by working to common business and technical visions. In short, disciplined agile professionals are "enterprise aware".
- Delivery teams don’t need prescriptive process definitions BUT they do need some high-level guidance to help organize their work. Individual IT professionals are typically highly-skilled and highly-educated people often with years of experience, and teams of such people clearly have a wide range of knowledge. As a result of this knowledge it is incredibly rare for such people to read detailed procedures for how to do their work. However, they often still require some high-level advice to help them to organize their work effectively. Teams can often benefit from techniques and patterns used by other teams and this knowledge sharing should be encouraged.
- IT professionals know what to do BUT they’re still not process experts. A decade ago the strategy was to provide detailed process advice to teams, but recently the pendulum has swung the other way to provide little or no defined process at all. Over the last few years there’s been a trend within the agile community to advise teams to define their own process so that it’s tailored to their own unique situation. While this clearly strokes people’s egos, it’s relatively poor advice for several reasons. First, although every team is in a unique situation there is significant commonality so having at least a high-level process framework from which to start makes sense. Second, although these teams have a wide range of knowledge it might not be complete, nor consistent, nor is it clear what the trade-offs are of combining all the really good techniques that people know about. There is significant benefit in having a flexible process framework such as DAD which shows how everything fits together.
- IT professionals should validate their own work to the best of their ability BUT they likely aren’t testing experts so therefore need help picking up the appropriate skills. The mantra in the agile community is to test often and test early, and better yet to test first. As a result agile teams have adopted a “whole team” approach where the development team does its own testing. This works when there are people on the team with sufficient testing skills and more importantly can transfer those skills to others. Minimally you will need to embed testers into your delivery teams, but you should also consider explicit training and mentoring of everyone on the team in testing and quality skills. You may find my agile testing and quality strategies article to be an interesting read.
- Disciplined agile teams work in an iterative manner BUT still follow a lifecycle which is serial over time. On any given day people on a DAD project team may be performing analysis, testing, design, programming, deployment, or a myriad of other activities and iterating back and forth between them. But, the DAD lifecycle includes three distinct phases which are performed in order. So, DAD is both iterative in the small but serial in the large.