Although stretching should be a part of everyone's workout program, few people actually do it on a regular basis.

A complete workout program should include cardio workouts, resistance training, and stretching. When you combine the three you maximize the effects of your workouts.

The benefits of stretching are well established. They include increased range of motion, which improves performance, fewer injuries, and quicker recovery after workouts.

Typically people do a short period of stretching at the beginning or end of a workout, but research has shown that doing flexibility work before a workout is actually counter productive. The best times for flexibility work are either at the end of a workout, as part of your cool down, or else later in the day.

Flexibility work done late in the day (for example in the evening while watching TV) is a great way to relax and unwind before bed, and ensures that the muscles are warm and ready.

If you want to put together your own routine, there is a great variety of books available. Some of the choices include:

Stretching by Bob Anderson
The Anatomy of Stretching
Stretching Scientifically: A Guide to Flexibility Training
Ultimate Flexibility: A Complete Guide to Stretching for Martial Arts
Stretching for 50+: A Customized Program for Increasing Flexibility, Avoiding Injury, and Enjoying an Active Lifestyle