Clinical drug development has changed significantly over the past decades. Supported by great advances in the discovery phase, it has enabled a plethora of options and opportunities to capture the clinical benefits and risks associated with the administration of these compounds in all disease areas. An overview of types of clinical trials, different phases of drug development, targeted drugs/companion diagnostics and biomarkers, and various basic considerations/principles will provide the reader with a peek into the options and considerations during the clinical phase of development of a pharmaceutical intervention.