Pharmacist interventions constantly face the difficulty adapting to a suitable experimentation model. The following paper discusses such difficulties within the context of randomization. Given the fact that the method is not always dependable, or even applicable; it is suggested that a "quasi-experimental" approach be taken, such as non-randomized and at time non-controlled. Provided herein is an outline of available quasi-experimental methods with their pros and cons. Their use and potential in the pharmaceutical field is explored in detail for the benefit of researchers.