Membe served as a national security analyst at the President's Office from 1978 to 1989.
He thereafter attended Johns Hopkins University in Washington, D.C. where he studied international relations from 1990 to 1992.
In 1992, he was assigned to serve as an Advisor of the Tanzanian High Commissioner in Ottawa, Canada, where he served until 2000.

In 2000, he was elected as a CCM member of parliament representing Mtama constituency in the general election.
He was re-elected in 2005 and 2010.
He was appointed as Deputy Minister of Home Affairs by President Jakaya Kikwete after the 2005 general elections.
After a cabinet reshuffle in October 2006, he was appointed as Deputy Minister of Energy and Minerals .

In January 2007, he was appointed as the Minister of Foreign Affairs and International Co-operation after his predecessor Asha-Rose Migiro was appointed as the United Nations Deputy Secretary-General by the U.N. Secretary General Ban Ki-moon.
He has also served as a member of the National Executive Committee of the ruling Chama Cha Mapinduzi party since 2007; having been re-elected in 2012 at the 8th CCM Congress in Dodoma.

In January 2013, Membe informed his constituents that he would not be vying for a seat in the next parliamentary elections in 2015 thus giving rise to speculation that he may be considering to run for the presidency.

In February 2020, the CCM's central committee expelled Membe from the party after accusing him of " indiscipline and violating the party's ethics and constitution".
 He has denied wrongdoing and said he was expelled because he wanted to stand for nomination as the party's presidential candidate.

In July 2020 he handed back his CCM membership card.
 Later that month he joined the opposition Alliance for Change and Transparency (ACT) and said he was willing to stand as its candidate in the presidential election in 2020.
Membe served as a national security analyst at the President's Office from 1978 to 1989. He thereafter attended Johns Hopkins University in Washington, D.C. where he studied international relations from 1990 to 1992. In 1992, he was assigned to serve as an Advisor of the Tanzanian High Commissioner in Ottawa, Canada, where he served until 2000.
In 2000, he was elected as a CCM member of parliament representing Mtama constituency in the general election. He was re-elected in 2005 and 2010. He was appointed as Deputy Minister of Home Affairs by President Jakaya Kikwete after the 2005 general elections. After a cabinet reshuffle in October 2006, he was appointed as Deputy Minister of Energy and Minerals .
In January 2007, he was appointed as the Minister of Foreign Affairs and International Co-operation after his predecessor Asha-Rose Migiro was appointed as the United Nations Deputy Secretary-General by the U.N. Secretary General Ban Ki-moon. He has also served as a member of the National Executive Committee of the ruling Chama Cha Mapinduzi party since 2007; having been re-elected in 2012 at the 8th CCM Congress in Dodoma.
In January 2013, Membe informed his constituents that he would not be vying for a seat in the next parliamentary elections in 2015 thus giving rise to speculation that he may be considering to run for the presidency.
In February 2020, the CCM's central committee expelled Membe from the party after accusing him of " indiscipline and violating the party's ethics and constitution".  He has denied wrongdoing and said he was expelled because he wanted to stand for nomination as the party's presidential candidate. 
In July 2020 he handed back his CCM membership card.  Later that month he joined the opposition Alliance for Change and Transparency (ACT) and said he was willing to stand as its candidate in the presidential election in 2020.
Bernard Membe