Sectional pressure groups seek to represent the common interests of a particular section of society. As a result, members of sectional pressure groups are directly and personally concerned with the outcome of the campaign fought by the group because they usually stand to gain professionally and/or economically. Trade unions, employers’ associations and professional bodies are all sectional groups. The National Union of Teachers (NUT), the Society of Motor Manufacturers and Traders, the British Medical Association (BMA), the Confederation of British Industry, Trades Union Congress and the Law Society are examples of sectional groups.

Because sectional groups are solely concerned with a particular section of society, membership is usually restricted to, for instance, lawyers, teachers etc. Since the aim is to look after the interests of all the people in that section of society, sectional groups tend to aim to get as many eligible members as possible to join the group.