If you are losing the control of your Information System because of its complexity, it is time to apply its “golden number” four (4). You have to think and communicate around the “4” as a holistic commitment. All your processes, deliveries, organization rules must apply the principle of the “4” as stated below. It is simple to share, free of charge and will make your working processes healthier. As a decision maker, facing a delivery out of the “4” golden number should be seen as an alert about a likely useless complexity in your IS.
 
Process governance

• Maximum 4 steps in a process
• Maximum 4 types of actors in a process

 
Data governance

• Maximum 4 transitive relations from a core business object
• Maximum 4 states in a business object’s life cycle (not included start and end states)
• Maximum 4 nested data levels in a data flow (root counts as one level)
• Maximum 4 levels in the data lineage process (copy of data between systems)

 
Rules governance

• Maximum 4 business input parameters in a rule
• Maximum 4 business output parameters in a rule
• Maximum 4 transitive calls from a main rule

 
Data quality

• Maximum 4 matching fields for a policy
• Maximum 4 business KPI for a business object
• Maximum 4 business objects for a dashboard

 
User Interface

• Maximum 4 UI steps in a end-to-end UI process

 
IT organization and software engineering

• Maximum 4 members in a team
• Maximum 4 deputy staff per manager
• Maximum 4 weeks for a sprint
• Maximum 4 key features in a sprint
• Maximum 4 months to deliver a new version
• Maximum 4 iterations on a prototype

 
IT software

• Maximum 4 tools or frameworks per IT layer
• Maximum 4 IT layers (Data & Integration, Rules, Process, UI)