How to use click data to: 1) improve relevance calculations 2) improve recall by extending returns 3) customise, personalise & diversify returns 4) exploit collective knowledge and make recommendations 5) respond, adapt & evolve Overall, a form of self-organising “Knowledge Map”, built and applied from the bottom up. Click data enables simple, flexible, scalable methods that can run at query time. Using click data to adjust query returns results in an ongoing implicit feedback process and easy significant improvements. This requires no models, external data, large sparse matrices, clustering, machine learning etc., and helps deal with many of the usual problems associated with collaborative methods. For further detail see http://www.slideshare.net/pontneo/better-search-implementation-of-click-through-filter-as-a-query-parser-plugin-for-apache-solr-lucene