This volume continues the story of teh National Research Council begun by Physics at the National Research Council of Canada (also written by Middleton) and Biological Sciences at the National Research Council of Canada (by N.T. Gridgeman). Technical enough to interest the scientifically informed reader, yet comprehensible to the general reader, this history of the development of radar in Canada by the N.R.C. in the years of the Second World War explains what radar is and how it functions, and briefly describes at the problems which led to the development of new equipment--such as the need to detect mortar bombs and the danger of airborne attacks on Canadian coasts. The author describes how personality clashes, tensions between co-operating organizations, and difficulty administrative puzzles were overcome, allowing scientific expertise to triumph in the speedy and valuable development of new radar devices, an important contribution by Canada to the war effort. The volume is well organized and includes illustrations. Documentation from government sources, use of quotations from correspondence and interviews, personal reminiscences of the author, and informed opinion and interpretation combine to make the volume easy and information reading.