The present technology relates to a control device, a method for control, a program, and a projection system that enable to, in a case where input information is to be presented by projecting an image, naturally attract the attention of a person around a projection surface. A control device of an aspect of the present technology projects an image representing input information onto a projection surface so as to follow an input of the input information, with an effect in accordance with the type of the projection surface. As the projection surface, a thin sheet material attached on a wall surface is prepared, for example. The color of the thin sheet material is a dark color, for example, and in time with projection of the image representing a handwritten character or picture, a sound, which will come out when the character or the picture is drawn with a chalk on a chalkboard, is output from a speaker installed on the back side of the projection surface. The present technology can be applied to a system that presents information by projecting an image from a projector.