The purpose of this study was to establish ecological validity and initial construct validity of the virtual reality version of the Multiple Errands Test based on NeuroVR software as an assessment tool for executive functions. In particular, the Multiple Errands Test is an assessment of executive functions in daily life which consists of tasks that abide by certain rules and is performed in a shopping mall-like setting where there are items to be bought and information to be obtained. The study population included three groups: post-stroke participants (n = 9), healthy young participants (n = 10), and healthy older participants (n = 10). The general purpose of the study was investigated through the following specific objectives: (1) to examine the relationships between the performance of three groups of participants in the Virtual Multiple Errands Test (VMET) and in the traditional neuropsychological tests employed to assess executive functions; and (2) to compare the performance of post-stroke participants to those of healthy young and older controls in the Virtual Multiple Errands Test and in the traditional neuropsychological tests employed to assess executive functions. Correlations between Virtual Multiple Errands Test variables and some traditional executive functions measures provide preliminary support for the ecological and construct validity of the VMET; further performance obtained at the Virtual Multiple Errands Test provided a distinction between the clinical and healthy population, and between the two age control groups. These results suggest a possible future application of such an ecological approach for cognitive assessment and rehabilitation of stroke patients and elderly population with age-related cognitive decline.