Liang, Y.-Z., Manne, R. and Kvalheim, O.M., 1992. Constrained background bilinearization. Chemometrics and Intelligent Laboratory Systems, 14: 175–184. A new constrained optimization method is presented for background bilinearization of two-way multicomponent data. Constraints come from the positivity of spectral intensities and concentration. The convergence properties of the proposed method, called constrained background bilinearization, is tested by a series of simulations. The results compare favourably with a modified version of residual bilinearization, mainly because the constrained method is superior in locating the global optimum in the presence of local optima.