This article reviews research conducted after the American Academy of Pediatrics 1999 recommendation against screen exposure for children less than 2 years old. Television in the background disrupts play and parent-child interactions. Background TV exposure is associated with negative cognitive and language outcomes. Children begin to understand conventional age-directed TV programs between 1½ and 2½ years old, after which TV can be educational. Before about 2½ years, learning from TV is less than learning from equivalent real-life situations. Although TV exposure before 2 years old is associated with slower cognitive and language development, most of that research does not separate age-directed TV content effects from adult, background TV effects.