Efficient blue light generation by SHG for use in optical storage etc. requires materials that display not only a large nonlinear response and but also optical transparency at the wavelengths of both the laser and the blue light. New chromophores containing sulfonamide, sulfonate, or sulfoximide groups are described that come nearer to this ideal. The optical transparency of electron-donor and electron-acceptor substituted conjugated pi systems studied previously, which was found to be poor owing to a low-lying charge-transfer absorption, is shown to improve when the acceptor group is sulfonamide or sulfonate ester.