Despite cutting-edge CAD and AI technology, design and hand drawing remain an essential part of the design process and gives buildings their charm and humanity. Watercolour drawings serve the purpose of getting the colour key right for the building as well as giving the patron and craftsman a very clear idea of what is as a crucial way for discussing ideas with a client. The ability to draw rapidly using tools of trade in front of a client to show how things might work is an essential part of conceptual thinking. More polished drawings are also useful to show how a proposed building will appear when completed. Tools of trade allow us to communicate vaguely and precisely at the same time.