The Medical Science Liaison (MSL) role was recently reported as one of the best jobs over six figures for healthcare professionals, yet is relatively unknown, even to the medical community. What is a medical science liaison, and what do they do? In this comprehensive must-have guide to the role, the functions of the role of MSL are explored, along with interviews with several MSLs, those that work around them, and most importantly, the customers of the MSL, academic thought leaders. Every healthcare professional, from a pharmacist, to a PhD, to a MD should learn more about one of the greatest jobs that blend business with technical and scientific acumen.