Shelby, B. and T. A. Heberlein. 1986. Carrying capacity in recreation settings. Corvalis: Oregon State University Press.

This book develops a general conceptual framework for carrying capacity in recreation management and research. Social carrying capacity is viewed primarily as a way to merge research and management traditions concerned with establishing appropriate use levels in terms of both crowding and natural resource deterioration. The framework includes descriptive elements of use levels, evaluation of recreation systems, and management standards. The authors tackle the issue of lack of correlation between crowding and satisfaction and density and perceived, and conclude that normative standards offer more effective for making capacity judgments. Setting capacity levels, however, does not solve the allocation issue. Setting use levels does not solve the question of the appropriate mix of recreational users and the authors present two basic allocation mechanisms. Recreation conflict is often attributed to both of these dimensions: crowding and competition between different use types.

Stankey, G. H. and S. F. McCool. 1984. "Carrying capacity in recreational settings: Evolution, appraisal, and application." Leisure Sciences 6(4): 453-473.

This article reviews the literature on the carrying capacity concept and its application to recreation management. Written largely has a defense of the carrying capacity construct, it argues that essential elements of the carrying capacity were recognized early including: 1) recreationists seek multiple satisfactions from recreation and, depending upon these, encounters with others might add, detract, or be neutral in their effect on those experiences; 2) satisfaction is a function of more than use level - the type, frequency, and location of encounters are important intervening variables; 3) clearly stated objectives are essential to identifying carrying capacities; and 4) the emphasis in management needs to be on the outputs - the experiential and environmental conditions desired - not on the inputs such as use levels. The article allows reviews critically the research on the relationship, or lack of one, between overall satisfaction and number of encounters. The authors speculate that a number of mediating factors at play include: 1) self-selected nature of recreation participation; 2) shifts in clientele and experience definition; 3) multiple influences on satisfaction; 4) how satisfaction is defined and measured; 5) saliency of use levels; and 6) the role of expectations and preferences. The article concludes that management focus should not be on "how much is too much", but instead on what kinds of conditions are appropriate and acceptable in different settings. They propose a "limits of acceptable change" as a management framework.

Heberlein, T. A. and B. Shelby. 1977. "Carrying capacity, values, and the satisfaction Model: A reply to Greist." Journal of Leisure Research 9(2): 142-148.

The paper examines issues relating to the measurement of visitor satisfaction levels and the relationship to establishing carrying capacities in recreation management. The article find that is impossible to set carrying capacities based on satisfaction levels as there are no mean differences in the satisfaction levels associated with different use levels. Other factors, such as peoples' choice to pursue the activity and their expectation of enjoyment, choosing to recreate elsewhere, or changes in individuals' tolerance for crowding, may have significant influence on satisfaction levels. Furthermore, the "satisfaction" model assumes a bivariate relationship between satisfaction and user densities, which is not an accurate depiction of the complex nature of the recreation experience. Management of recreation areas for maximum satisfaction is simply not an appropriate yardstick, as radical options like building a parkway along the Grand Canyon may actually result in higher total levels of satisfaction (due to increase in visitor numbers). Rather, recreation management is about defining appropriate goals for different recreation areas and then setting capacity levels that will achieve those goals. Similarly, goals for acceptable conflict levels allow managers to choose appropriate management action.