This paper discusses the design and implementation of the Islay Land Use DecisionSupportSystem (ILUDSS), aknowledge-basedspatialdecisionsupportsystem for strategicland-use planning in a rural area. ILUDSS is designed to support planners in assessing land-use potential for different types of land-use for the development of the island of Islay, off the west coast of Scotland. The system adopts knowledge-based techniques in its design, and incorporates analytical, rule-based and spatial modelling capabilities. The main functions of ILUDSS include query, formulation of land-use models for assessing land-use potential, and evaluation of the land-use models through automated integration of the database, the rule bases, and different types of models. ILUDSS can evaluate land-use potential according to planners' preferences and assessments relating to the various criteria and related evaluation factors, such as physical suitability, proximity to desirable and undesirable land features, and the required minimum area of each land parcel.