A clinical approach to the vexing problem of diagnosis of panniculitis is traced in this paper, in order to obtain from the clinical findings, history and laboratory data of the patient useful, detailed and precise information, essential to address dermatologists to a specific clinical diagnosis of panniculitis. This approach is created in the same way as when a dermatologist faces any other dermatological disease, be it inflammatory or neoplastic. A common behavior in case of panniculitis is in fact just to take an adequate biopsy and wait for the pathologist report. This is indeed a limitation both for the dermatologist and above all for the pathologist, who is in tremendous need for detailed clinical information before signing his report. The most common types of panniculitides, taking into account their main clinical diagnostic criteria, will be considered. In particular, Erythema Nodosum, Panniculitides in Sarcoidosis, Pancreatic Panniculitis, Lupus Panniculitis, Erythema Induratum/Nodular Vasculitis and Weber-Christian Panniculitis/Rothman-Makai Pannicultis will be analyzed. Every chapter will consider general criteria (epidemiology, age and gender, distribution of the lesions, laboratory findings) and specific findings (characteristics of the lesions, i.e. redness, pain, tenderness, evolution, ulceration, sites of involvement) as well as comorbidities and systemic signs and symptoms. Detailed analysis of the general criteria integrated with the specific findings will allow the clinicians to reach a clinical diagnosis with a high degree of confidence.