Topical therapy is one of the foundations of dermatology. The vehicles used to deliver topical therapy have considerable impact on efficacy. The vehicle can have direct effects on disease; it can impact the delivery of the active drug, and its characteristics affect patient compliance. While the physical chemistry of vehicles has been studied in great detail, there has been very little study of patients' preferences for different vehicles and even less on the effect of these preferences on patient compliance. Such study is essential, as noncompliance with topical therapy is very common, and likely impacts the response to topical therapy observed in clinical practice. This manuscript discusses information on patients' preferences for different vehicles, focussing on the treatment of scalp psoriasis. Significant vehicle characteristics such as ease or difficulty of use, messiness, odors, and staining are recognized to affect patients' preferences. An instrument based on these characteristics has been used to compare patients' preferences for different vehicles. Patients with psoriasis generally prefer less messy vehicles, such as foam and solution preparations, to traditional cream and ointment vehicles. These preferences have the potential to impact patient compliance. Studies directly measuring patient compliance have not yet been performed. In conclusion, the choice of vehicles impacts both the potency of the medication and patients' acceptance of the treatment. Actual effects of different vehicles on compliance are important but have not yet been adequately studied.