||This thesis is a synchronic study of the derivation of ordinal numerals from cardinal numerals in several different dialects of Dutch, combining a dialectological and a formal linguistic approach. Ordinals are formed with one of two ordinal suffixes, -de or -ste, both of which occur in all Dutch varieties. However, there is variation among several dialects in Flanders (Belgium): they exhibit stem-suffix combinations which differ from those in Standard Dutch (SD), giving forms like zeven-ste and twaalf-ste for SD zeven-de and twaalf-de. The thesis investigates the patterns of this variation and offers motivations for those patterns. Novel data acquired through an online questionnaire show that there are three patterns: SD, a core Flemish pattern and a transitional pattern in between. These patterns show a clear geographical distribution. I propose that the distribution of the two suffixes can be largely explained by syllable weight in the transitional system and that an analysis in terms of the final stem consonant or in terms of foot weight cannot capture all the facts.