Functionalised second-order nonlinear optical (NLO) polyimides have been developed. The key challenge in our approach was a one-step synthesis of these polymers, by reaction of di(hydroxyalkyl) chromophores and diimides utilising the Mitsunobu reaction. Glass transition temperatures in the range of 205-224degreesC were obtained. Thin spincoated films of the polymers were corona-poled and analysed by second-harmonic generation; values for d(33) of 30 pm/V were obtained. Poled order stability measurements over periods of 210-500 It resulted in 70-90% of remaining NLO-response at 125degreesC.