In the field of experimental psychopathology, clinical trials are useful to investigate causality, treatment options, and other clinical phenomena. Despite its common use and its position in the field as being “the golden standard”, RCT’s suffer important drawbacks and ethical challenges. For instance, for some treatments or phenomena, running a (randomized) clinical trial is simply not feasible. Therefore, alternative designs (e.g., N=1, repeated single case) have gained popularity in recent years. Such designs allow answering similar questions as randomized controlled trials and allow a more process-pure analysis of the therapeutic process or phenomenon under study. During the symposium, expert speakers will focus on the benefits, pitfalls, ethics of common clinical trials and discuss alternatives like N=1 and ecological studies.