Many organizations are now considering using a web content management software (CMS) product to facilitate the effective management of web sites and intranets. With many hundreds of open source and commercial CMS products to choose from the process of establishing requirements and selecting the best product for the long term can be both complex and risky. The implementation itself also needs to be managed with care, especially where there is a considerable volume of legacy content to be migrated to the new system. This paper provides an introduction to the benefits and challenges of content management software. It emphasizes that it may take a year from the time that the decision to assess the requirements for a CMS is taken to a full and effective deployment. The costs of implementation are also outlined, as these are invariably significantly greater than the CMS licence cost.