Quality assurance is important in the development and conduct of a suc
cessful single-site clinical trial. The successful principal investiga
tor (PI) is one who aligns him/herself with a knowledgeable team with
demonstrated capabilities in all aspects of clinical trial design and
execution including professionals with expertise in biostatistics and
experimental design, research administration including budget preparat
ion and proposal submission, patient recruitment and contact, data col
lection, data analysis, and computers. The effective PI will become an
effective coordinator of these functions by assembling this team, est
ablishing a realistic schedule, and demonstrating enthusiasm, integrit
y, and leadership. The team, as it is being assembled, and which typic
ally includes nonphysicians, will find helpful an explicitly enlarged,
detailed statement of the proposed hypothesis. This statement may inc
lude the type of patients to be studied, duration of the proposed obse
rvation period, and the methods of evaluation. Careful planning is the
best assurance that a successful and worthwhile study will be accompl
ished.