Crystal Methodologies Summary

Crystal Methodologies

Crystal Methodologies is a family of methodologies developed by Alistair Cockburn.[1] The word “Crystal” refers to the degree of hardness and the different colors of the methodology in much the same way that a crystal can have various degrees of hardness and variety of colors. The degree of hardness pertains to the use of rigor and ceremony i.e. as the hardnessincreases the amount of required documentation, processes and procedures increases.[6] The color is concerned with the “heaviness” of the project; the lighter the color the fewer the number of people on the project whereas the darker the color indicates the requirement for more resources. [1]

There are two “core" elements of the Crystal philosophy. The first core element is that software developmentcan be viewed as a game of invention and communication with the main goal being to develop useful, working software. The second element is the setup for the next game to follow. Members of the Crystal methods share values and principles and on-the-fly tuning.[1] All of the Crystal methods are highly people and communication centric and recognize the varying human cultures.

The two rules thatare common to all the Crystal methods are as follows:
1. The project must use incremental development with increments of four months or less with a string preference of one to three months
2. The team must hold both pre- and post- reflection with a strong preference for mid-project reflection workshops [1]
One of the restrictions of the Crystal methods is that they only address collocated teams.Thus, the Crystal methods would not apply to distributed or offshore teams for which Cockburn offers no recommendation other than to locate the team together at one location.

As was previously mentioned the Crystal methods are denoted by colors. The color of the methods as follows: Clear, Yellow, Orange, Orange Web, Red, Magenta, and Blue. Only three of the methods – Crystal Clear, Orange andOrange Web - have been constructed and actually used on projects. The Crystal methods can actually be considered to be a sort of family and visually arranged in a cube as illustrated in Figure 1. [5]

[pic]

Figure 1 The Crystal Methods (fr: The Crystal Methods or How to make a methodology fit
Alistair Cockburn, Agile Development Conference, 2003)

In Figure 1, moving tothe right on the X axis the number of the people on the project increases which result a decreased amount of face-to-face communication among team members. This also means that a heavier methodology must be used. The Y axis denotes the system’s potential for causing damage and range from loss of comfort to loss of life. In terms of the crystal analogy this means that the degree of “hardness” ofthe project increases as one move up the Y-axis. The outside world dictates the required elements in the methodology and the resulting deliverables for projects in the upper range of the Y-axis. Projects of this type include medical projects regulated by the FDA, projects for aircraft and air traffic control regulated by the FAA, etc. The Z-axis reflects the different priorities such astime-to-market, cost reduction or legal liability. The boxes on the grid indicate the class of projects in which the size, criticality and objectives intersect. In terms of the “color” metaphor, the C6 and D6 boxes are named for Crystal Clear, although admits that it could be stretched to include the E6 box. The C20, D20 and E20 boxes are grouped under Crystal Yellow, the C40, D40 and E40 boxes aregrouped under Crystal Orange and C100, D100 and E100 are grouped under Crystal Red. Crystal Magenta and Crystal Blue would encompass even larger projects.

Crystal Clear

Crystal Clear is for projects in the C6 to D6-category in Figure 1 but can be stretched to include projects in the E6 box. In Crystal Clear there is only one team of six people or less located in one office or adjoining...