Attention-deficit/hyperactivity disorder (ADHD) is one of the most common psychiatric disorders in children and adolescents, with up to 5 % affected worldwide. Twin and family studies on ADHD show its high familiality with heritability estimated around 70 %, but, to date, no specific polymorphism or gene was found to be specifically affected. Psychostimulants (amphetamine, methylphenidate) and non-psychostimulants (atomoxetine) are used successfully in ADHD therapy, but many of their mechanisms of action and their adverse effects are not yet fully understood. Therefore, both genetic findings and therapeutic interventions should be further investigated. One easy platform for such studies is in vitro analyses, which encompass neuronal cell culture studies, transfections of genetic constructs, binding and electrophysiology analyses. In this review, different methods will be referred in particular to ADHD findings, and new techniques will be mentioned for future studies of drug or genetic effects in vitro.