The landscape is an important contributor to quality of life. People identify with landscapes and landscapes contribute to a sense of place and wellbeing. Changes in land use activities, such as agriculture, and in current spatial planning policies and practice accelerate the transformation of landscapes as many new elements are superimposed upon traditional landscapes, altering their visual appearance. These changes may have profound influences on people?s quality of life. The visual landscape should therefore be given explicit attention in landscape planning and policy making. An important landscape characteristic is landscape openness. It is defined as the amount of space perceivable to the viewer which illustrates the importance of the interaction of people with their environment. Landscape openness is an important characteristic and a measure of attractiveness. In the Netherlands landscape openness is one of the features of the visual landscape and is also one of the core qualities of the National Landscapes, which have to be protected or enhanced. Landscape openness is vulnerable for changes is the landscape and monitoring the effect of landscape changes on openness is therefore essential for policy makers and planners. Current methods to measure landscape characteristics such as landscape openness either are suitable for policy makers but not reflect essential characteristics of the phenomenon, or accurately reflect the phenomenon but are not suitable for policy making and planning. Current improvements in measurement techniques, enabled by GIS, and the availability of highly detailed topographic data covering large areas make it feasible to describe landscape openness with a higher degree of realism, while making few concessions to generality and objectivity. Procedures and methods used in previous studies to describe landscape characteristics like landscape openness for policy making and planning purposes do not take full advantage of these improvements. The objective of this thesis is to develop a procedure which takes advantage of these improvements, but also produces a sound description of landscape openness and meets the required standards for policy making and planning. We formulated three research questions: 1: How can landscape openness be measured? 2: How well does the measured openness correspond with perceived landscape openness? 3: Is the measured openness relevant for landscape policy makers?