According to Williams, a pressure group is defined as ‘…a group of like-minded individuals who are organised with a view to influencing the formulation of government policy’. An indisputable definition of a pressure group, however, is very problematic, due to the several varying forms that they take, which perhaps explains why several pressure group definitions appear nebulous. The term ‘pressure group’ is relatively recent, yet ‘voluntary organisations’ have been attempting to influence policy ever since the late 18th Century. A typical example of this is The Society for Effecting the Abolition of the Slave Trade. This was founded in 1787 under William Wilberforce, and successfully achieved its objective to abolish slavery in 1807. In more recent times, pressure groups have flourished, despite having a fluctuating popularity. This is perhaps due to an increase in the access points available in the British political model and to the extensive opportunity for views to be put forward through the media. Pressure groups can be classified in two different ways; by what they aim to achieve, and how they attempt to achieve it. The former of these categories is split into sectional and promotional groups. Sectional groups act on behalf of a particular area of society. They are narrow-minded and are found mainly in the economic sphere of society. Promotional groups exist to promote a particular cause. They are less likely to sustain any longevity, as their issues are often resolved, and are mainly found in the environmental sphere of society. The latter category is split into insider and outsider groups. Insider groups have strong links with the decision makers within government and are regularly consulted. This means that they can gain access to the decision makers and put forward their case directly. Outsider groups, however, do not participate in the consultation process, mainly by government exclusion, but occasionally by choice. Most outsider groups aim to achieve insider status, for the opportunity to exert more influence. A third group in this category are prisoner groups. These have insider status not by choice but by necessity. The effectiveness of a pressure group is mainly dependent on the support it is likely to receive. Thus, the way in which a pressure group is represented varies greatly, with many groups claiming a larger potential membership than their active one. An example of this is the British Field Sports Society, who in 1995, had approximately 80,000 active members, forming their vocal minority. In addition to this, they claimed a silent majority of 5.5million affiliated sportsmen and women nationwide, forming their potential membership. Mass membership at active level is important if a group wishes to make a media impact, yet whilst often catching the public´s imagination, large-scale demonstrations, marches, or strikes do not necessarily lead to influence. As Bacon states, ‘Knowledge is power´; pressure groups need to have greater knowledge of their objective than the government, to allow them to achieve or retain insider status. To gain access to the decision makers, pressure groups must have credible authority. The National Union of Mineworkers (NUM) was a good example of this, as for a number of years, nearly 100 per cent of miners were spoken for by this group. After the1983/4 miners´ strike and formation of the breakaway Union of Democratic Miners in 1985, the NUM was weakened by its diminished representation. For influence, the group obviously has to have objectives that will be compatible with those of the government, unless overwhelming public support is obtainable. A classic example of this is the Trade Union Congress (TUC) and the Confederation of British Industry (CBI). The trade unions have traditionally been able to exert greater influence under the control of a Labour government than a Conservative one when pressing for favourable trade union legislation or state intervention in industry. Under Thatcher, the trade unions were treated with hostility and contempt, with their membership being diminished by 25% during the eighties due to the lack of access and influence the group was able to enforce. The opposite is true for the CBI; although Thatcher was an anomaly and rarely conversed with them either, the CBI were able to capitalise on the demise of the trade unions. The availability of access points is determined by the structure of government, party strength and government openness. The structure of the British political system, with its unitary state and limited separation of powers, is relatively closed, with restricted access available for pressure groups to obtain. This is in direct contrast to the USA, with strong federal and state governments, as well as a strict separation of powers. This creates numerous access points, and allows pressure groups to form Political Action Committees (PACs), to influence policy through donating money to a candidate´s campaign. Despite some well-exploited loopholes, these funds are limited to avoid one particular group, organisation or company obtaining excessive influence. This practice, however, is not the orthodoxy in Britain. Although large donations must be declared, there is no specific upper limit to the extent of a group or individual´s generosity to a political party. Evidence of this was apparent in the run-up to the 1997 General Election, when the Labour party was offered £1 million from Bernie Ecclestone, the Chief Executive of the FIA. Thus, when the issue of tobacco sponsorship legislation was addressed in the Commons after the election, it was little surprise that its abolition was set back five years. Local government in Britain is very dependent on central government, due to its reliance on central government for financial support, and its statutory powers being derived from Parliament. This means that at local level, pressure group activity will be directed at the way authorities implement central policy. Therefore, issues such as local transport and land development will be directed at local level. However, former Environment Minister Nicholas Ridley once referred to British localised pressure groups as having ‘NIMBY (Not In My Back Yard) syndrome´, suggesting that these localised groups are only trying to restrict development in their area, rather than concerning themselves with the issue as a whole. Although Parliament is bicameral, the usefulness of the House of Lords to a pressure group is minimal, due to its vastly diminished power. Private members´ bills, however, can often be very effective in promoting the aims of a pressure group. An example of effective pressure group activity behind a private members´ bill was the Abortion Law Reform Association, who campaigned for the liberalisation of abortion law in 1967. It is also possible for pressure groups to gain access to the executive and the judicial branches of government, yet this is less common. A radical example of judicial pressure was exerted by the Anti-Poll Tax movement between 1989 and 1991, through the adoption of a civil disobedience policy, culminating in a refusal to pay the community charge. They were taken to court and imprisoned, yet received huge publicity and support for their cause. It is clear from the development of pressure groups that they seek only to influence policy rather than control it. Pressure groups are forced to use different methods depending on who they are and what kind of status they have. This can occasionally lead to certain pressure groups obtaining a bad press, such as the IRA, who have attempted to influence policy through violence and terrorism. These acts are usually committed out of desperation, when influence has become almost impossible to obtain. It is arguable that pressure groups, particularly outsiders, create media attention out of weakness rather than strength, as they are unable to exert influence effectively with their existing level of support. Greenpeace, through their highly publicised demolition of fields of genetically modified crops in September 2000, have accentuated this notion, after being initially unable to persuade the government to suspend such production. Insider groups, which win acceptance by the government, have a privileged position over the outsiders on the periphery. Despite the attempts of Thatcherism to diminish the activities of pressure groups (particularly those from the economic and socio-economic genres), contemporary post-modernist Britain is providing a healthy catalyst for increased pressure group activity within democracy, specifically allowing environmental groups to flourish in both influence and popularity. Furthermore, with the European Parliament´s ever-increasing role as a decision-making institution, the scope for the development of ‘eurogroup´ activity is equally promising.