Evidence based estimating

Evidence Based Scheduling from Joel on Software

Using Evidence-Based Scheduling is pretty easy: it will take you a day or two at the beginning of every iteration to produce detailed estimates, and it’ll take a few seconds every day to record when you start working on a new task on a timesheet. The benefits, though, are huge: realistic schedules.

Realistic schedules are the key to creating good software. It forces you to do the best features first and allows you to make the right decisions about what to build.