THE Transpacific Westbound Rate Agreement (TWRA) managing director Ronald Gottshall will leave the organisation in September. Mr Gottshall, who was instrumental in forming the rate-making group, served as its first line chairman, representing Sea-Land Service, Inc, from January 1985 until he assumed the post of full-time managing director in September 1985. ''Ron Gottshall has been an effective administrator, balancing shipper and carrier needs during a difficult period for the conference system,'' said TWRA executive committee chairman Richard Murphy. ''His experience in the Pacific and his overall understanding of pricing issues affecting our trade have been extremely valuable to the agreement.'' Mr Gottshall, from San Francisco, has served in the transportation industry for 36 years, initially with the Southern Pacific and the Illinois Central Railroads. He joined Sea-Land in 1963 and held various pricing positions in Japan and Hongkong, culminating in the job of Pacific division pricing director at Sea-Land's New Jersey headquarters. During Mr Gottshall's tenure, the westbound liner trade doubled in volume, to about 27 million tonnes annually, with an expanding cargo mix and unique service characteristics. TWRA itself weathered a number of challenges in the westbound market, including sustained over-capacity, increased competition from independent carriers and regulatory challenges from organised shipper interests. Mr Gottshall said he intended to remain active in the transportation industry. ''We accomplished what we set out to do in terms of establishing a new, more flexible kind of ocean conference under the 1984 Shipping Act and putting that conference on firm footing,'' Mr Gottshall said. ''Now is a logical time for a change of leadership. We're seeing a new, more complex market emerge which presents fresh opportunities for dialogue and creative pricing approaches among shippers and carriers.''