With rapid advances being made in sensor technology, wireless sensor networks (WSNs) have emerged as an essential source of data for storage and processing on highperformance computing grids. The significant amount of data generated by sensor networks requires preprocessing at the source-end, to ensure reduction in the total volume of data generated for transfer and storage in highperformance grid systems. There exists a lack of an infrastructure for optimal and efficient retrieval of sensor data through grid-sensor integration, and facilitation of efficient sensor resource sharing in environments with multiple WSNs. In this paper, we propose the Secure Grid-Sensor Integration Architecture (SGSIA), as a secure, scalable, and intelligent architecture for the integration of resourceconstrained sensor networks into the grid.