The purpose of this research was to empirically validate the daylighting and economizer facets of the DOE-2.1E building simulation software with an actual building. The test facility where these validations exercises were performed was the Iowa Energy Center's Energy Resource Station (ERS). Weather information measured at the site was used to build weather files in a TMY (Typical Meteorological Year) format. Input files containing specific information about the structure, system and equipment, and control strategies of the building were used in conjunction with the building simulation software. Coupled with the site weather information, predictions were made for system and zone performances. These predictions were then compared to the empirical data that were taken at the ERS. The predictions for the controls strategies were integrated within a whole building analysis to quantify the impact and interactions within the zones and system. Both validation efforts were performed using a variable-air-volume system with terminal hydronic reheat (VAVRH). For the daylight tests, a diffuse window treatment was used. DOE-2.1E prediction for the lighting power to the test rooms closely matched the light power. Illuminance predictions at the reference point were generally very close to measured values, except when relatively high magnitudes of ambient light entered the space. With the exception of the zone reheat predictions, zone and system predictions closely matched the empirical quantities. Problems with room stratification in one of the tests lead to discrepancies in the reheat power required for the space. The system temperatures, cooling heat transfer rates, and supply temperature were comparable to the empirical parameters. Comparisons for the economizer control were only made for the system. In general, the predictions for parameters like outside airflow rate, supply airflow rate, cooling heat transfer rates, and system temperatures were comparable to the empirical parameters.