Some embodiments of the invention provide a configurable integrated circuit (IC) that has several configurable circuits for configurably performing different operations. During the operation of the IC, each particular configurable circuit performs a particular operation that is specified by a particular configuration data set for the particular configurable circuit. While the IC operates and a first set of configurable circuits performs a first set of operations, configuration data is loaded from the outside of the IC for configuring a second set of configurable circuits. In some embodiments, the configurable IC includes a configuration network for rapid loading configuration data in the IC from outside of the IC. In some of these embodiments, the configuration network is a pipelined network. Also, the IC of some embodiments includes a configuration controller for retrieving configuration data from outside of the IC, formulating configuration data sets, and routing the configuration data sets to the second set of configurable circuits over the configuration network.