The consequences of visitor use for natural resources is a common management concern in parks and protected areas. Managers are often charged with maintaining park resources in perpetuity while simultaneously allowing for an unconfined visitor experience. In order to meet this challenge, there is widespread agreement that monitoring trends in visitor use and resource condition is essential to inform the best management decisions. Designing, conducting, and processing information from monitoring programs is often a difficult charge, however, and all too often managers need to make decisions without adequate monitoring data. The problem is often exacerbated by an incomplete understanding of visitor impact issues that invariably include ecological and human dimensions.