Social policy draws on sociology to explain the social context of welfare provision. If we are trying to improve people's welfare, it is helpful to try to understand something about the way that people are, and how welfare policies relate to their situation. Some writers have gone further, arguing that because welfare takes place in a social context, it can only be understood in that context. This has been particularly important for 'critical social policy', which begins from a view of social policy as underpinned by social inequality - particularly the inequalities of class, race and gender. Issues of inequality are considered in a companion file on Welfare and equality.
Societies are 'structured' in the sense that people's relationships follow consistent patterns. Fiona Williams has argued that social policy is dominated in practice by the dominant values of society - the issues of family, work and nation. 
Family A range of policies are built around the idea of the 'family' as a man, woman and children. Examples are child benefits, education and child care. Some countries have policies built on the idea of the man as 'breadwinner', with support based on the idea that the marriage is permanent and the woman will not work. Families which deviate from the norm - for example, poor single mothers - are likely to be penalised, though there may also be anomalies in the organisation of benefits (e.g, when promiscuity is accepted and stable cohabitation is not).
Work Many systems of social protection depend on a stable work record for basic cover in unemployment, ill health and old age. Workers who misbehave - for example, by striking or being dismissed - may be penalised.
Nation Most systems discriminate against non-citizens, and many have residence rules for particular benefits or services. Immigrants are likely to have different, and often second-class, services.
These issues are discussed further in the sections which follow.
"Normal" does not mean "average"; it means "conforming to social norms". The 'normal' family consists of two parents with one or more children, but it is increasingly untypical in developed countries. Several factors have contributed to this trend:
Social policies sometimes seek to reinforce the normal family, by rewarding normal conduct or penalising "deviant" (non-normal) circumstances. Rewards include subsidies for married dependants and children; penalties include requirements to support one's family, and legal and financial deterrents to divorce. At the same time, the assumption that couples live more cheaply than single people may lead to two single people getting greater support: cohabitation rules, treating people living together as if they were married, are used to ensure equity with married couples.
The rise in lone parenthood is mainly based on three factors:
There is no reason to attribute the rise to teenage motherhood (which, like other forms of motherhood, has tended to fall).
The position of lone parents who receive social benefits has been controversial. The liberal individualist position is that if people choose to have children it's then up to them to look after their family. The collectivist position, and to a large extent the dominant position in continental Europe, is that children are other people's business as well. There is also a strong body of opinion which considers that the interests of the children override any moral concerns about the status of the parents.
Teenage pregnancy was the norm in previous generations, but it has become more common for women to delay childbearing. The reasons for the delay, and for falling birthrates, include
Teenage pregnancy is highest when these factors do not apply to the same degree. This accounts for the apparent association of some social problems with teenage pregnancy.
The incorporation of people into the formal labour market has been central both to policies to deal with poverty and exclusion, and to the development of social protection. However, in many circumstances people are only partly integrated into the labour market. Their situation is characterised as
Economic marginality has implications for social inclusion. Unstable economic conditions lead to social instability - marginal employment is associated with family breakdown - while also reducing the level of social protection available.
Many welfare systems have their origins in collective and mutualist actions by trades unions, professional or occupational groups, rather than the state. Trades unions developed, for example, unemployment benefits in Denmark, social housing in Norway, or the health service in Israel. In France, social protection for unemployment is administered by a "convention" of employers and trades unions.
It is also true that welfare developed historically at a time of social conflict, and labour organisations have had an important role in the development of policy, including Bismarck's establishment of social insurance and the foundations of the British social services. Marxists have traditionally seen the welfare state as the outcome of struggles by the labour movement. This is only true in part: several measures - like insurance-based pensions in the UK - have developed despite the resistance of organised labour, and others, like the extension of rights to the poorest, have been marked by conflicts between groups.
Nations are seen at times as groups linked by a shared history or culture; as a collective group of people in a specific geographical location, with a common identity; or as political communities. Historically, social welfare became important shortly after the rise of "nation states", and in some views the ideas are closely associated. David Miller, for example, argues that the nation is the principal community on which welfare provision depends. 
National identity is as often used, however, to exclude people from welfare as to promote inclusion, and the influence of nationalism on welfare has tended to be negative. Titmuss criticised the idea of the "welfare state" because it seemed to limit the scope of welfare to a particular locality.  Universalists have promoted an inclusive concept of welfare; in principle, this concept is inclusive, but in practice it tends to be confined to citizens, or members of the political community.
Immigrants, by definition, come from outside a community; wherever social protection depends on contribution to collective welfare, immigrants are liable to be excluded. Residual income support may be available, but it is unusual for non-contributory benefits, such as benefits for disabled people, to be available directly to immigrants; many countries have some kind of minimum residential qualification.
Much immigration consists of movements of people from poorer countries to richer ones: immigrants tend to come with relatively limited resources. Few countries offer immigrants a full range of social protection or benefits, and in the short term this is likely to lead to disadvantage. At the same time, migrants tend to be younger and more mobile than host populations. In the longer term, much depends on the economic niche occupied by immigrant groups, and their relative status and resources. Immigrant careers are highly differentiated.
Issues of immigration overlap with racism. However, there are racial minorities who are not immigrants and widely persecuted (like the Roma in central and Eastern Europe), and some immigrant groups are not disadvantaged.
Social policies can be seen as collective responses to social problems. A problem is social when it is socially recognised: important issues like grief and emotional distress are not necessarily 'social', and there may be no social policies to deal with them. Conversely, other, seemingly minor, concerns and complaints can be elevated to the status of social problems, and acted on - dealing with 'NIMBY' protests ('not in my back yard') bedevils community care provision.
Problems are 'socially constructed'. People's values, beliefs and opinions are conditioned by the society they live in, and people come to share many basic perceptions. This can shape the way people think about issues, and close off some options: so, child abuse is usually constructed as the result of parental abnormality, and not as the obvious outcome of rules which allow children to be beaten physically.
Deviance refers to a breach of social rules, or 'norms'. Normal behaviour is behaviour within these rules. There are many possible explanations for deviance. The main schools of thought include
The literature on deviance includes material not just on crime, but on many other issues which are seen as 'problematic', such as disability, sexuality and illegitimate births.