This book is intended for use by interns, junior residents, first year medicine PG residents and non Medicine PGs/SRs as a comprehensive guide for their OPDs and to help clear doubts related to management and approach to common diseases. This book helps to understand the practical aspects of treating the most commonly seen, simple diseases which can and should ideally be treated by any MBBS graduate at the primary healthcare level. We all know what the biggest flaw in our medical education is: Immediately after MBBS, we know the theory of everything but the practical aspect is largely ignored (both by the system as well as the students who are keen on mugging up facts for the post-graduate entrances). Students know the pathogenesis and genetics of the rarest of the rare diseases but lack confidence in treating and approaching common diseases like diarrhoea, hypertension, hypothyroidism etc. This book gives an idea about basic treatment protocol to be followed as per standard guidelines and more importantly, tells when to refer to a specialist. Red flag signs when OPD treatment should not be continued at the primary care level have been mentioned wherever appropriate.