Pitfalls in traditional project scheduling and execution - solution: Critical Chain

1. Critical Chain Project Management Fred Wiersma TTI-30 June 2000

10. Example: Bad Multitasking Task A Task B Task C Tasks assigned to a resource 3 days 3 days 3 days Should happen : Task A Task B Task C 3 days 3 days 3 days Could happen: B B A A C C 6 days 6 days 6 days Does happen : B B A A C C 7 days 7 days 7 days Lost Productivity

16. Manage the Project Buffer Okay Plan Act 0% 33% 66% 100% Percent Buffer Consumed Percent Critical Chain Remaining 100% 67% 33% 0% Manage on buffer status with respect to work completed

18. Updating Tasks Design : “ We completed the 2-day task, but we still have 4 days to go on our other task” Proto : “ We haven’t had a chance to get to our task" Project Report CC Complete: 15% PB Consumed: 30% Copyright © 1999 by ProChain Solutions, Inc. All rights reserved. 2 Dev 2:Dsn 3:Proto 4: Dev 2:Tst 6.5: Project Buffer 2: FB 5:Design Today Projected task times Buffer consumption Projected task time

20. Multi-Project Scheduling 1 2 1. Set projects at their due dates 3. Collect drum resource tasks 5. Reschedule projects Drum Schedule 4. Resolve drum contention 2. Select the drum resource(s) 2 Dev 2:Dsn 3:Proto 4: Dev 2:Tst 6.5: Project Buffer 2: FB 5:Design 2 Dev 2:Dsn 3:Proto 4: Dev 2:Tst 6.5: Project Buffer 2: FB 5:Design 2 Dev 4: Dev 2 Dev 4: Dev 2 Dev 4: Dev 2: FB 5:Design 2 Dev 2:Dsn 3:Proto 4: Dev 2:Tst 6.5: Project Buffer 2 Dev 4: Dev