If you are a consultant, isn't it professional indemnity insurance that you require? I only say this as consultancy sounds like an advice only service. I may be on the wrong line here though???

PL insurance is a requirement from my major clients. They want to know that I have sufficient resoources to fund the claim after I drop the proverbial spanner in the works, or handkerchief in the soup or manage to poke their employee's eye out with my sound level meter or fill the MD's roof-down MGB with sprinkler drain water (only once, in 1976).