Effect of shading, ventilation, and a combination of these for cooling honey bee, Apis mellifera L., hives during summer months were studied under field conditions at Tucson, Arizona. Mean brood nest temperatures during day hours, 0800 to 2000 hrs., were significantly lower in shaded and ventilated colonies than those of all other treatments. Neither shading alone nor ventilation alone had a significant effect on brood nest temperatures compared with control treatment. Nectar and pollen carrier proportions were significantly larger in shaded colonies than those of unshaded colonies at 1400 hrs. Ventilation had insignificant effect on nectar carrier proportions in both locations, whereas it significantly decreased and increased pollen carrier proportions in shaded and unshaded colonies, respectively. Mean volumes of nectar, however, were not significantly different from each other in all treatments. Proportions of water carriers and water volumes were significantly smaller in shaded colonies without significant difference between means of ventilation and no ventilation than those of unshaded colonies with ventilation had significantly smaller means. All treatments were not significantly different from each other regarding mean numbers of departing bees at 0900, 1100, and 1400 hrs and mean sealed brook areas. Mean colony weight of control colonies differed insignificantly from those of all other treatments. In another study, empty bee hives made of pine wood, perlite concrete, and sun-dried adobe and subjected to different combinations of shading and painting were tested to determine the effect of these materials thermal properties in cooling and heating the hives during summer and winter, respectively. The walls of the wooden hive were 1.9 cm-thick while those of the other two hives were 5.0 cm-thick. Under all treatment conditions, the areas under the curves for inside air temperatures of the wooden hive were larger than those of the other two hives for a 10-hour period, from 0700 to 1700 hrs. The calculated "temperature areas" for the other two hives were very close to each other. Shading was more effective than white paint in reducing hive temperatures in summer. Hives painted black during winter had remarkably higher temperatures than white-painted hives.