In December 1984 Paias Wingti and his faction within the PANGU Pati lost out in a reshuffle of Michael Somare’s cabinet. In March 1985 Wingti resigned from PANGU and challenged Michael Somare’s Prime Ministership in a vote of no confidence. The motion was defeated and the 14 PANGU members who had supported it were expelled. On 28 March 1985 the expelled members formed a new political party, the People’s Democratic Movement (PDM), under the leadership of Wingti with Nahau Rooney as Acting General Secretary. Any differences in ideology or policy between the PDM and PANGU were not apparent to outsiders. In November 1985 Somare was defeated in a vote of no confidence. Wingti became Prime Minister and his PDM headed a five-party coalition.
In 1987 the PDM fought on a platform of support for agriculture and an appeal to the highlanders to keep a highlander as Prime Minister. Wingti retained the Prime Ministership after the 1987 elections but lost to PANGU’s Rabbie Namaliu in a vote of no confidence in July 1988. In July 1992 Wingti defeated Namaliu (55:54) and formed a Coalition Government of the PDM, People’s Progress Party, the League for National Advancement and Independents. The PDM’s policies in 1992 included revitalization of commercial agriculture, improved rural services, an open economy actively involved in international trade, increased participation of PNGans in the modern economy, privatization of statutory bodies, promotion of manufacturing, free primary school education and commitment to ”good government”. In October 1993 the PDM had 25 parliamentary members.