I am giving this a 4 star rating because it is a well presented collection of sketches from artists who enjoy drawing out of doors, in cafes, or in public buildings. I am not giving it a four star rating for its instruction on how to sketch. That part is a little, well, sketchy. I think this book is aimed at readers who already draw or have the inclination to do so, already. The sketches are numerous and varied in style. Some are urban, some are rural, some are of the human form. Many are hastily drawn in a matter of seconds or minutes, and the author is certainly encouraging rapid, spontaneous drawing while on site, perhaps while waiting for transportation. Others are more painterly or detailed. The purpose seems to encourage artists to draw frequently and habitually, and to get outside and experience the energy and freshness that working en plein air provides. There are examples of perspective and architectural drawings, contrasted with some very primitive fast sketches. I think some of the illustrations are chosen as examples of how to draw rapidly moving objects or to convey a sense of atmosphere. There is little instruction in how to draw...mostly inspiration to get out there and make a mark.