In 30 seconds
- Crystal is a family of methods, not one framework.
- The right variant depends on team size and how critical the system is.
- Core ideas: frequent delivery, reflective improvement, close communication.
The idea
Alistair Cockburn developed Crystal in the 1990s after studying what successful teams actually did. His conclusion: there's no single right process. Small, low-risk teams need very little ceremony; large teams building critical systems need more.
A family, sized by colour
Variants are named by colour, from Crystal Clear for small co-located teams of up to about eight people, through Yellow, Orange and Red for larger groups. Higher criticality, such as risk to money or lives, adds more rigour.
Core properties
- Frequent delivery of working software
- Reflective improvement after each cycle
- Close, "osmotic" communication, with people near each other
- Personal safety to speak up
- Focus and easy access to expert users
Myth vs reality
Myth · Crystal is outdated.
Reality · Its ideas of sizing process to context remain widely used.
Myth · Crystal has strict rules.
Reality · It's deliberately light; teams tune it.
Myth · Only Crystal Clear matters.
Reality · Clear is best known, but the family idea is the point.
FAQ
Who created Crystal?
Alistair Cockburn, one of the Agile Manifesto authors.
Is Crystal still used?
Rarely by name, but its principles show up in many teams.
How does it compare to Scrum?
Scrum prescribes roles and events; Crystal prescribes properties and leaves the rest open.