| April 1977 | National Federation of Fisheries Co-operative Associations (until March 1985) |
| April 1985 | Secretary to Mr. Zenko Suzuki, Member of the House of Representatives (HR) |
| February 1990 | Elected to the HR (39th General Election) |
| March 1990 | Chairman, Promotion Division of the National Campaign Headquarters, Liberal Democratic Party (LDP) (until November 1991) |
| November 1991 | Director, Committee on Judicial Affairs, HR (until January 1993) |
| July 1993 | Elected to the HR (40th General Election) |
| August 1993 | Director, Special Committee on Disasters, HR (until January 1994) |
| September 1993 | Deputy Chairman, National Campaign Headquarters, LDP (until March 1995) |
| July 1994 | Director, Special Committee on Disasters, HR (until September 1994) |
| July 1994 | Director, Local Organization Bureau of the National Organization Committee (Until March 1995) |
| July 1994 | Director, Committee on Communications, HR (until October 1994) |
| October 1994 | Director, Committee on Health and Welfare (until September 1996) |
| October 1994 | Director, Fisheries Division, LDP (until October 1996) |
| February 1996 | Deputy Director-General, Personnel Bureau, LDP (until October 1996) |
| October 1996 | Elected to the HR (41st General Election) |
| November 1996 | Parliamentary Vice-Minister of Health and Welfare (until September 1997) |
| August 1998 | Director, Social Affairs Division, LDP (until October 1999) |
| June 2000 | Elected to the HR (42nd General Election) |
| December 2000 | Deputy Chairman, Policy Research Council, LDP (until January 2001) |
| January 2001 | Chairman, Committee on Health, Labor and Welfare, HR (until January 2002) |
| January 2002 | Deputy Secretary-General, LDP |
| January 2002 | Director, Committee on Health, Labor and Welfare, HR |
| September 2002 | Minister of the Environment |
