In the years since Raúl Castro took office as president following Fidel Castro's illness and retirement, Cuba has embarked on four major transitions almost simultaneously: a restructuring of elite decision-making; a transformation of Cuba's centrally-planned economy into a market socialist economy; a relaxation of tight social control, providing greater social autonomy for civil society and even a degree of political decompression; and, a transition from the founding generation of the political elite (los históricos) to a successor generation, when neither Castro will hold power. Each of these processes by itself entails political risk; unfolding together, they constitute the greatest political challenge the Cuban regime has faced since the collapse of the Soviet Union.