Lightsolve is an innovative tool that offers architects and lighting engineers a goal-based simulation platform for daylighting performance evaluation in early stages of building design. Users can import their own 3D model and define their own design goals for a comprehensive spectrum of daylighting performance perspectives regarding task illumination, visual comfort, overheating risks, health effects and visual interest of a space. The tool provides key information to the designer that is easy and intuitive to grasp thanks to a combination of unique, visual and interactive graphical display formats. Available visualization options include photo-realistic renderings, full-year temporal performance representation as color maps, and spatial performance distribution through false-color renderings. Both model orientation and localization can be user-defined, and weather data (e.g. TMY) can be used to get climate-specific results. Accuracy is ensured by the usage of the ubiquitous and extensively validated Radiance simulation tool.