Use a third-party firm to administer the survey, to ensure independence.Survey your established clients, your target clients, and those who you've pitched to unsuccessfully.Survey regularly and as a matter of course - try to survey after every project or, if unrealistic for your organisation, for every project over with fees over £x.Just as important as the survey process is: the feedback process - so that consultants and managers get timely feedback (relatively soon after the project); and the feedforward process - so that survey questions get refined to suit your firm's evolving business development initiatives and strategies.