June brides have always been popular but now more than ever it seems wedding bells are in the air.

Whether it is elegant royals in European cathedrals, shimmering celebrities on the covers of OK! or Hello! or feckless grooms and dismayed fiancées in Don't Tell the Bride, weddings have never been bigger or better. As Scotland marks the 10th anniversary of humanist weddings, it is time to reflect on what is happening.

This fashion for weddings is surprising given that marriage has long been in decline. In Scotland, as throughout Europe, marriage rates have fallen dramatically since the 1960s. While 43,696 marriages were registered in Scotland in 1968, by 2013 the number had fallen to 27,547. Marriage-based families are the most common family type in the UK, but cohabiting couple families are the fastest growing, increasing 30 per cent in the last decade. Marriage may be less popular, but weddings are big business.

Scotland has a long established reputation as a wedding destination. It offers not only outstanding venues but an accommodating legal framework, giving couples flexibility and choice. Scotland's marriage laws have always been more liberal than those of its neighbours, making it the "go to" place for couples in a hurry to marry.

Throughout Scottish history the age limits have been low: it was not until 1929 that the canon law ages of 12 for girls and 14 for boys were raised to 16 for both. Parental approval has never been a legal requirement, and visitors and tourists have always been welcome, with little legal attempt to apply residence criteria.

The long survival in Scots law of various forms of irregular marriage allowed couples to marry before the sheriff, over the anvil or indeed on their own, without the presence of celebrant or witnesses, by means of the simple exchange of spoken consent. Irregular marriage was only finally abolished in Scotland in 2006. Over the centuries, Scots law has made it easy for couples to marry.

Once more, Scotland is becoming the place to marry. Increasingly what couples want is Scotland's newest form of ceremony: a humanist wedding. The first humanist celebrants, from Humanist Society Scotland (HSS), were authorised in 2005 and since 2014 humanists, together with other belief organisations, have had their own statutory category of belief marriage. Scotland now has three types of legally recognised wedding: civil, religious and belief. Similar calls to give legal authority to humanist marriage in England have so far been foiled by a much more complicated and constraining legal system. While the Law Commission of England and Wales is only now embarking on a review of the law relating to marriage ceremonies, in Scotland humanist marriage is already celebrating its 10th anniversary.

From a relatively modest 425 marriage ceremonies conducted by HSS in 2006, the figure in 2014 reached 3,361 and numbers continue to grow. In 2010, humanist weddings outnumbered those solemnised by the Catholic Church and HSS predict that they will soon overtake the Church of Scotland.

The ease with which humanist and other belief weddings have become established in Scots law says much about the law's flexibility: a regulatory framework open and responsive to the needs and wishes of individuals. Marriage nowadays is less about a social and legal institution and more about personal commitment. This individual vision of marriage is expressed in the way couples shape their wedding ceremony to make it their own. It is exactly what humanist weddings offer: no fixed model of what marriage is or should be but a belief in the celebration of human life.

As wedding fashions change, their place in the framework of family law becomes less settled. When marriage was a clearly defined institution and being married was the only legitimate basis for living together, the wedding offered legal certainty: a marker of changed status and a sensible point at which to attach legal rights and obligations.

But as weddings become more personal, their legal meaning is more difficult to discern. When they are celebrated not as a precursor to conjugal life but after many years of established cohabitation, their significance shifts. Scots family law has much to celebrate in the success of humanist weddings but it may yet need to reflect on what they tell us about modern relationships and how they should be regulated.

Jane Mair is Professor of Private Law in the School of Law, University of Glasgow.