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ore important than others, and some are strategically critical. Examples of such strategic portions and positions include the inlets and outlets of a basin and breaks in a corridor that have critical values for ecological processes (Forman and Godron, 1986; Merriam, 1984); the conspicuous land marks, narrow defiles, gorges and bridges that have significant visual perceptual effects (Stein and Niederland, 1989; Tuan, 1974); as well as certain places that have a strategic significance for economic processes (Taaffe and Gauthier, 1973). It is important to note , however, that in some cases various processes in the landscape may be controlled by spatial patterns that are not intuitively obvious nor visually apparent to a human observer. It is assumed that some kinds of thresholds exist in the trajectories of the dynamics of processes. At some points (in terms of number, size, shape and inter-distance of landscape elements), a slight change in landscape property produces sudden changes in the response of the process. Such thresholds have been recognized in urban development (Kozlowski, 1986). Similar to thresholds, other co ncepts have been proposed that may also be useful in understanding my ideas concerning the strategic landscape and security patterns such as safe minimum standards (SMS) (Bishop, Fullerton, et al, 1974; Ciriacy-Wantrup, 1968), carrying capacity, and ultimate environmental thresholds (UETs) (Kozlowski and Hill, 1993), etc. It is thus reasonable to assume that: (1) landscape patterns associated with these critical thresholds or constraints are likely to be strategically critical in controlling or promoting certain processes; (2) landscape design and management following these strategically critical patterns can more effectively safeguard or control the processes. Therefore, it is worthwhile to identify and apply SPs in landscape planning. The following two aspects of exploration become the major focus of this paper: (1) How can we define and identify SPs and what are they? (2) How can we apply SPs in landscape planning to achieve a less detrimental landscape, while at the same time, maximally making changes acceptable to decision makers and/or developers? These two aspects of inquiry compose an approach to landscape planning which I call the SP approach, or the approach of security patterns. It is an approach to defending various processes of our concern, aiming at a good balance of acceptable changes and a securer landscape through identifying and applying security patterns (SPs). The SP approach tries to establish 'stop signs' in the procedures of decision making for various landscape changes, and to safeguard the security of the processes at critical points. In a certain sense, defining SPs is a strategy of spatial defense, an operational weapon of negotiation aimed at a less harmful change by controlling critical points, or 'frontiers'. Defense by these SPs is expected to be more effective in safeguarding the landscape processes of our concern. GIS has great potential when combined with the SP approach in landscape planning and decision making (see Yu, 1995c for more detailed discussion on the SP concept). A case study of the Red Stone National Park in south China, is used to illustrate the SP approach. This case is selected since it dramatically represents a defensible procedure of landscape change among defenders of three interacting, and often competing, processes in landscapes, including ecological, visual a