This chapter discusses understanding the contribution of milk constituents to the texture of dairy products, specifically focusing on liquid milk products. It starts by examining the viscosity of milk, reviewing flow behaviour models and the effect of milk composition and temperature on milk viscosity. The chapter moves on to discuss the viscosity of concentrated milks and examines the composition and temperature of these milks and the role of whey proteins and minerals. The effect of preheating concentrated milks on viscosity is also discussed. A section on ultra-high-temperature milk texture is also provided, which is then followed by a section on the texture of fat-containing products. The chapter also discusses the perceived texture of milk and the effects of non-thermal technologies on milk and dairy products.