This article examines the concepts of a "contingent" creditor and a "prospective" creditor in the Companies Act and the Companies (Winding Up) Rules 1969 in the light of existing case authority. In the process, it attempts to define the outer boundaries of these concepts. Some practical considerations and problems in making a claim against a company as a contingent or prospective creditor are also examined. Particular attention is paid to the problem of proving non-contractual claims for unliquidated damages in the winding up of the insolvent company.