Using a bivariate ordered probit model, this paper examines the effects of house ownership, housing tenure, income, household size and composition, and the occupation and education of the make and female head of household on ownership of cats and dogs. Large households have more of both, but other factors differ between cat and dog ownership. Women's opportunity costs and missing female adults encourage cat ownership. Cats and dogs are slightly complementary. A GMM demographic specification test does not reject normality. The data are taken from a demographic scanner panel data set developed for a marketing study.