Dear Jigs, thanks for your answer, but my problem is not about the difference between duration and work, I know it very well. I’ll clarify my problem: Task A is planned with a duration of 5 days, I assign resource X, then it has a work value of 40 hours. Later, when the task is finished, I ask resource X all details. He says: I did the job in 4 days, but I still spent 40 hours on it. Now that is something that cannot enter in MS Project Tracking table: when I modify ‘actual duration’ in 4 days, it recalculates ‘actual work’ to 32 hours, when I modify ‘actual work’ back to 40 hours, it recalculates ‘actual duration’ back to 5 days, etc… So I just want to enter the correct values for actual duration: 4 days and for actual work: 40 hours. I cannot see how.