The contemplation of the reorganisations of the Australian Defence Group of departments over the past 34 years led to a notion that for organisations operating in turbulent environments there may exist a hypothetical re1ationship between perceived environmental uncertainty and organised complexity. This hypothetica1 relationship is described as 'coping' and is based on an assumption that in an organisational setting, individuals make some form of response to changes in their environment and this response is manifest in organisational change. The notion of this hypothetical relationship also led to the development of two 'ideal type' models - the Coping Model and the Overload Model. The application of contingency theory through the Overload Model showed that the State of an Organisation could be defined acccrdicg to its mode of existence in relation to some optimal level of information processing and some optimal level of organised complexity. A typology of ths States of Organisations has been derived from the Overload Model and design strategies which are appropriate to each state have been ranked according to an ordinal preference scale. The 'ideal type' models have allowed subjectively weighted judgements to be made about the present state of the Defence organisation and the ranking of design strategies to avoid the perceived undesirable state of overload. The Department of Defence is now imputed to be in a state of 'disorganisation'. The Overload Model suggests that there has been an over-investment in vertical information systems at the expense of lateral relations. The policy-making implication of this suggestion is that the state of 'overload' can be avoided through a reduction in organised complexity and the creation of lateral relations. This can be achieved if the Central Office is restructured to reduce the number of committees and if appropriate co-ordinating representatives are placed in the Service Offices.