In our increasingly complex and dynamic world of business, the roles of expert professionals – and the rules and rewards for success – are now under sustained scrutiny.There is no shortage of knowledge or research about principles or theory of leadership. And, there’s a plethora of advice on corporate leadership. But excellent leadership in the professional services sphere is substantially about understanding, embodying, and being through and through that which both clients and other seasoned professionals choose to follow.Once as a priestly caste with unassailable privileges, social status, and economic advantage, professional success has now moved on. Great professional practices are built on behaviour. And I observe that the pattern of choices and decisions around leadership behaviours substantially determine destiny.What clients want mostMany thousands of words could be written on the subject of what clients of professional services firms – lawyers, accountants, actuaries, architects, engineers, management consultants, and so on – really want. And, every client is different.But fundamentally, what clients want is:o leadership – professional services clients silently beg to be led and cry out for expert help in solving their problemso to be told what specific action to take in their interestso expert professionals to selectively sell their services to help clients with their problems, challenges, and opportunitieso their clients want to know what their professional advisors have done for them, and to appreciate what has been achieved on their behalfo clients need expert professionals to educate them in the benefits delivered and how to further leverage the worko their clients want to feel they are getting something more than just the routine treatment, are receiving “a little extra”o professional advisors who lead them through engaging expert helpo to discern and derive clear value in return for investment in professional help.Certainly, professional service firm’s clients want to buy expertise.Most of all, they want expert professional passion applied in their interests.And, with this firmly in mind, it’s the quality of the relationship with a professional advisor which so often determines the success of the relationship and yield for each party.Reliability builds crucial trustTrust is crucial to effectiveness and longevity of relationships between expert professional advisers and quality clients. Because trust is the product ofo predictability and dependabilityo understanding, acceptance and empathyo frankness, forthrightness and authenticityit is rarely “instant”, and generally builds over time.Trust goes way beyond mere rapport. Certainly, trust builds on shared experiences and shared values but it takes this to a different level. Being trustworthy is at its foundation.Because clients are not God and can not read the soul, they have to rely on what a professional says and does to work out whether they are worthy of their trust.To convey trustworthiness, the professional must:o do what she/he says they’ll doo take action within agreed timeframeso consistently meet deadlineso keep commitments to follow upo always follow through to check that things have gone wello take responsibility to deliver the solutions offered or promised.Consistently behaving in these ways builds trust with valued clients.Authenticity and frankness build crucial trustHumans have well developed “crap detectors”: some have remarkable capacities to work out who’s on the level, who’s not being completely frank or straightforward, and who’s not telling them the whole story.Strong professional services client relationships depend on the trust that develops in an open, frank, and truly authentic dynamic.This goes well beyond mere technical honesty and may at times call for the courage and gumption to speak fiercely.An expert professional can go a long way to building trust – and truly serving the client – by:o saying what they really think and believeo when necessary, giving the bad news clearly and unmistakablyo not hiding unpleasant facts, issues, or possibilitieso not playing political gameso admitting when they’ve made an error, got it wrong, or even changed their mindo being clear about their limitations.Showing the authentic, real whole, multi-faceted person to a client is not to be feared or avoided – expert professionals are far more believable and trustworthy when they show that they’re absolutely straightforward, forthright, and don’t shy away from bad news.Acceptance and empathy build crucial trustFor an expert professional, it is often really easy to see the foolishness, errors and poor choices which may have disadvantaged a client or led to some awful predicament.Trust with clients will be eroded by:o not taking time to understand and accept the client and their wider business and social environmento spending too much time and focus on their errors, poor decisions, or historical problemso attacking previous sources of advice and counselo having all the answers too quickly, without taking time to appreciate “why” as well as “what”.Professionals communicate acceptance and empathy when they:o respect the client’s point of viewo explore the impact of the situation on themo reassure them of genuine concern, sincere interest, and ability to assisto avoid any temptation to remind the client that had they enlisted your support earlier, they wouldn’t be in this (undesirable) situationo constantly emphasise readiness, willingness and enthusiasm to help.Clear the way to build strong trust as willingness to help is put into action.Reinforce crucial trustTrust won’t be built by just doing – even if ever so well – a few of the items covered here.Rather, trust grows from dynamic and complex interplay of openness and authenticity, acceptance and empathy, and reliability.How you put all these ingredients together will substantially determine the extent and quality of trust established with a client.Every so often, expert professionals must take stock. Evaluate based on these dimensions:o really being able to say what you believe, convincingly and completelyo telling clients the truth – the real story, avoiding nothingo what you say is what you do – avoiding hypocrisyo consistent follow through on offers, commitments, and promiseso you are tactful and kind to clients, but never shy away from telling it like it is and giving clients bad news, clearly and unmistakablyo you do not avoid conflicts, smooth things over, or tell part-truths only to have it all catch up eventuallyo you advise your client as you would expect and hope to be advised, should tables be turned.Lasting, productive client relationships are built on trust. To earn trust, above all, be trustworthy.And so it is that a professional will be entrusted with the privilege to apply their expert passion in their client’s interests, and gain at least as much as they give.