Extensive temperature microstructure measurements were obtained in August--September 1973 in the Denmark Strait between Iceland and Greenland during the experiment called Overflow '73. We have examined the average properties of the microstructure, such as variance and derived quantities (e.g., vertical eddy diffusivity kz) to establish typical levels of structure with respect to large-scale oceanographic features in this area. The measurements were obtained by using the vertical profiler Octuprobe with thin film thermometers to measure temperature gradient. This is an area with levels of microstructure 2 or 3 orders of magnitude higher than in other oceanic areas. It is a region of large horizontal variability and one where interleaving and frontal processes may be important. In our measurements we found no tendency for increased levels of structure to occur where double diffusion is possible. In comparison to bulk models, our measurements of vertical heat flux Q, using the Osborn-Cox model, suggest that diffusive processes may be important in the formation of Norwegian Sea water. On the other hand, diffusion processes appear to be negligible in comparison with entainment in the Overflow stream.