This paper examines the costs of the establishment and operation of FOI legislation in the Tasmanian, Victorian and Commonwealth jurisdictions focussing on the experience of the Tasmanian Forestry Commission. The term 'costs' was interpreted widely to include financial costs and other problems experienced by those working within the FOI framework, for example pressure on staff, and loss of frankness and candour.The costs are analysed in general terms and with particular reference to the Forestry Commission. The benefits of FOI are then weighed against the costs, and the difficulty of contrasting calculable costs with less easily calculated benefits is noted. The conclusion is that the costs must be considered in any evaluation of the effectiveness of FOI, but should not be allowed to overshadow the benefits.