Strong epidemiological studies clearly show that reduction in body fat content decreases the risk for many clinical conditions including diabetes, hypertension, coronary atherosclerotic heart disease and some forms of cancer. Therefore, detailed understanding of the mechanisms underlying how fat pads expand appears crucial. Extensive studies already identified a cohort of transcription factors involved in adipocyte differentiation but the fine interrelationship between the myriads of cellular and molecular events occurring during this complex biological process is far from being completely understood. Since the cloning of the first coregulator, the impact of those molecules has dramatically increased. In this review, we will summarize the emerging impact of coregulators on energy balance with a specific interest for fat formation. Emphasis will be given to the coactivators of the SRC (p160) family.