Clinical practice guidelines (CPGs) are suited tools for controlling and improving the effectiveness and efficiency of medical care. With the upcoming internet, the numbers of CPGs have increased rapidly, however, only few offer the attributes of good guidelines such as reliability/reproducibility, applicability, flexibility, clarity, multidisciplinary process, scheduled review and documentation of clinical and scientific evidence. Nearly identical criteria for appraisal of CPGs have been developed in many countries consisting of a checklist with questions concerning the quality of development, the content and format, and the applicability of the guideline. In the United States, guidelines which successfully passed the appraisal (or clearing) process, were stored in the National Guideline Clearinghouse, an internet-based database. A German counterpart is under construction, which will comprise clearing reports reviewing and appraising all existent guidelines covering a medical topic. Developing high-quality CPGs is a time consuming and expensive process. A widely accepted guideline for guideline development was published by the Scottish Intercollegiate Guideline Network. CPGs touching neurosurgical topics are rare and often developed without neurosurgical participation. Due to the potential medico-economic impact of CPGs in the future, national neurosurgical societies and their international associations should play a more active role in the development and implementation of CPGs.