This chapter provides an overview of survey methods, naturalistic observations, and case-studies as they are used in psychology. Survey methods are based on the simple discovery “that asking questions is a remarkably efficient way to obtain information from and about people”. Traditionally, survey content has been divided into two types: fact and opinion. Surveys are an extremely efficient means by which to obtain categorical information, the dimensions that people use to describe themselves: age, education level, employment status, and so on. Survey respondents are subject to the same memory biases as other people, including the representativeness heuristic and the availability heuristic. Administering a survey through face-to-face interviewing is time-consuming and expensive, and requires well-trained interviewers. The proportion of residences with telephones in most industrialized countries is so high that telephone interviews may well be the most preferred survey administration mode.