This Note reports on a study of the relationship between migration and fertility in Peninsular Malaysia. Using a unique body of retrospective data on both fertility and migration drawn from the Malaysian Family Life Survey (MFLS), it seeks to distinguish cause and effect in the statistical association between migration and fertility. First, the authors give some attention to levels of migration among women in Malaysia and to a short discussion of migrant/nonmigrant differentials in marriage patterns. Next, children ever born as the key dependent variable is examined. This approach will parallel assessments of previous analyses for other countries. The authors take advantage of the flexibility of the MFLS data by varying the definition of migration. As far as possible, controls are introduced for background variables, especially urban/rural residence, and assess migrant/nonmigrant differentials in use of contraceptives. The final section then uses the unique retrospective data available to analyze the temporal relations between migration and fertility.