Doing field studies: What is it all about?

Field studies provide much ecological validity but are limited with regard to randomization and control. What can be and what is done about it? Because so few psychologists do field experiments, little is known about it. In our reply to Wicherts and Bakker (in press), we show what goes on behind the scene in doing field research, and we discuss the importance of cumulative results by inclusive replications that cover strict replications, but also replications in different settings, using different paradigms.
Keywords: field experiments, littering behavior, methodology, norms, validity