The spliceosome is a dynamic, macromolecular complex, which removes non‐protein‐coding introns from pre‐mRNA to form mature mRNA in a process known as splicing. This ribonucleoprotein assembly is comprised of five uridine‐rich small nuclear RNAs (snRNAs) as well as over 300 proteins. In humans, several of the known proteinaceous splicing factors are members of the immunophilin superfamily. Immunophilins are peptidyl‐prolyl cis–trans isomerases that catalyze the conversion of proteins from cis to trans at Xaa‐Pro bonds. Our review of the data indicates that some members of this protein family are activators of spliceosomal proteins by way of folding and transport.