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A select committee is a small group of MPs (currently all have 11-13 members) appointed for the life of a Parliamentary session to consider specific topics. Unlike a Standing committee, which is larger and appointed to examine a particular Bill in detail, the select committees are free to chose the nature of their investigations within their subject areas. They are empowered to call witnesses and to elicit evidence. There are currently 17 select committees, constituted according to the standing orders of the House of Commons. They have wide subject areas, such as health, science and technology, and public services. Only back-bench MPs are included, in proportion to the parties' strength in the House. Select committees do not always reach agreement, and their reports only describe the majority view. However, minutes of their meetings are also published, so it is possible to gauge the level of dissent. For a report to be critical of a Government department, at least one MP from the party in Government must have agreed to such a publication.