The resurgence of big-ticket M&A will please many partners because the work runs throughout their entire practices, stimulating demand for several different services. Yet structural change can also have a traumatic effect on cash flow. There can be few events more disruptive than a key client becoming the subject of a merger or acquisition. Longstanding relationships can be lost as senior contacts move or lose out in organisational change; some practices lose lucrative contracts as work is consolidated under suppliers favoured by acquirers; others lose places on client panels.

For small firms, the effect can be catastrophic. They often have a foothold in a major company due to the preference of one individual. If that individual moves and if that income stream is a major percentage of the practice's income, hard times follow.

For instance, one small patent firm discovered that an individual was instructing it against company policy because their service was so good. Although this was a huge compliment to the partner involved, the firm had to initiate plans to obviate any loss of revenue if the individual moved, including developing relationships with others in the organisation. For the biggest firms, the stream of transactional work from banking clients can disguise the disruption. Yet displaced client-service teams can be hard to handle and the dip in cash-flow disruptive to earnings or investment plans.

Is the loss of key clients through structural changes inevitable? Does experience – or even science – exist that might offer a few helpful preventative insights? There are both 'soft' and 'hard' sides to this.

On the hard side is the approach to the client's formal purchasing function. Despite the use of legal panels by many large plcs, until recently many partnerships have had easy, informal, relationships with senior in-house counsel, who have been sceptical about the grounds on which their corporate purchasing specialists judge value.

Now, however, buying functions are starting to gain more influence and are applying more rigorous processes and controls to premium professional services. Starting with accountancy and high-end executive search, they are developing methods – now being applied to law – by which to determine price and value from the professions.

Hard facts

However, although formal purchasing can be difficult to handle in the event of structural change, it can be used to one's own advantage. Contracts, cancellation clauses and depth of process knowledge can be used to argue for continued supply. In fact, some partners have found that their formal position with an acquired entity has earned them the right to bid for business across the new organisation. In my view, much of the professional service industry is simply not equipped to handle the demands of formal purchasing. Investment in partner education on these techniques will pay back handsomely.

Another hard-headed aspect of maintaining client relationships during traumatic change is an objective and analytical understanding of the depth of exchange between the firm and its client. Many leading partners say that successful income generation is 'all about relationships'. Yet mutually-profitable relationships that stand the test of time have greater depth than mere friendly discussions, helpful informal advice and a free ticket to the occasional rugby match. They are also more than just excellent work executed well.

Evidence suggests that they rely on the degree of investment by both sides in mutually-profitable initiatives. On the client side, for instance, many in-house counsel see it as part of their job to invest time in educating worthy suppliers about their organisation, their strategies and their requirements. Busy people (even those who rarely go to corporate hospitality events or prefer a quick coffee to an expensive dinner) are willing to spend hours in helpful service reviews or strategy briefings in order to improve their suppliers' performance. If they are prepared to invest time in the relationship, so should the partners of their external counsel.

Perhaps surprisingly, this can be measured as proven techniques exist by which these relationships can be planned and the investment quantified. One such technique – the absolute risk reduction model, developed by academics – is a reasonably well-developed tool to plot, rate and understand the relationships a practice has with its clients.

The concept divides business relationships into three levels: actor bonds; activity links; and resource ties. Actor bonds are the interchange between principal people and activity bonds are the exchanges during work. Yet the third ingredient, resource ties, often underpins the relationship. In other words, they share non-project-specific capabilities to help each other for mutually-profitable results.

Resource ties are particularly important in securing long-term client commitment. Some leading firms, for example, loan professionals to clients to cover short-term needs such as maternity absence. Although this can be costly, the relationships they develop and the insight into the client can pay back in terms of profitable work. The benefit of this is confirmed by academia, with a study by US professor Leonard Berry finding that generosity was a prime ingredient in the success of leading service suppliers. In other words, the investment of time pays back, even if it is costly in terms of current billable hours.

Soft sell

The 'soft' side of relationship management is also critical during structural change. People do not, as some suggest, turn their emotions off at work. Executive decisions can be based on impressions, mood, belief and gut feel; strong emotions can also come into play during a major reorganisation, merger or acquisition. Some will feel excited by potential gain but many, even those at the highest levels, will be stressed or even scared. Taking time out to be supportive and acting as a sounding board or confidante to close clients can pay back in terms of lucrative contracts when the dust settles.

A clear-headed view of the client's politics is also important. Businesses are based on finance and people within them compete for limited resources. In all companies, there is a competition for ideas, policies and ambitions that uses both informal and formal influences to affect the development of the firm. Internal politics are therefore a common experience of every organisation and are a prime ingredient in managerial success that is exaggerated during significant changes. Political understanding is often the prime ingredient of a practice's success with a major client. Understanding the client's politics, perhaps by getting client relationship managers to construct a political 'map', will often help chart a course for the firm with changing clients.

If the latest City boom continues, some partnerships – both large and small – will suffer because their clients are acquired, merged or reorganised. Lead partners in firms with any depth of industry knowledge will know which key clients are likely to be an acquisition target. It is sensible therefore to invest a little time in anticipating a response, using both hard and soft techniques to obviate some of the damage.

Laurie Young is the author of Marketing The Professional Services Firm.