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A simple method for deriving [N/O] abundances is presented which is based upon models from CLOUDY (Ferland) and which requires the observations of optical [NII], [OII], and [OIII] lines. We show the self- consistency of the new method, and the agreement with more detailed modeling of individual HII regions. Gradients for well-observed galaxies in the Vila-Costas and Edmunds (1993) sample are presented, as are the discrepancies between the two methods.