The present book is concerned with numerical methods for problems of convective heat transfer. The material is divided into three parts. In the first part the basic numerical methods are considered solving the movement of viscous incompressible liquid. The alternating direction implicite method and the finite elements method are described. Systems describing convective heat transfer in terms of rotation and flux are treated numerically in the second part. In the third part the authors present numerical results solving some important problems in practical applications.