A buffer module is installed in a coating film forming unit block of a coating and developing system to reduce the number of interface arms needed by an interface block, and the manufacturing cost and footprint of the coating and developing system. For example, buffer modules BF31 to BF34 capable of holding a number of wafers W greater by one than the number of coating modules COT1 to COT3 of a COT layer B3 is installed in the COT layer B3, In the COT layer B3, a wafer W is carried along a carrying route passing a temperature control module CPL3, COT1 to COT3, a heating and cooling module LHP3, and the buffer modules BF31 to BF34. A main arm A3 carries wafers W such that the number of wafers W placed in the modules on the downstream side of the CPL3 is greater by one than the number of modules between the CPL3 and the buffer module when a processing rate at which an exposure system processes wafers W is lower that at which the COT layer B3 processes wafers W.