Decide when and where to record. You have two choices here, continuous recording or sampling. Continuous recording involves observing each occurrence of a target every time it occurs. Sampling...

Decide when and where to record. You have two choices here, continuous recording or sampling. Continuous recording involves observing each occurrence of a target every time it occurs. Sampling involves observing target behaviors for a sample of clients, situations, or times, depending on the information you need. The key principle of sampling is to try to get a representative picture of the occurrence of the behavior. Whatever type of sample is collected, though, you should try to standardize the time, place, and method used to observe, or it will be difficult to evaluate change over time. Establish clear and consistent guidelines regarding who, what, when, and where behavior is observed. (We discuss sampling issues in more detail in the following sections.)