Takabuki was a member of the 442nd Regiment, and fought in Europe during WWII. During the early 1950s, he served as president of the 442nd Veterans Club.
As an attorney, he worked with Chinn Ho on some of the largest financial and real estate deals in the Islands.
Takabuki was elected to the Honolulu City Council, then known as the Board of Supervisors, in 1952 and served the council for 16 years, a full eight terms.
Takabuki was former Hawaii governor John A. Burns' campaign organizer and later closest adviser.
Governor Burns pushed for the appointment of Takabuki by the Hawaii State Supreme Court to Board of Trustees of the Bishop Estate in 1971. All the members of the Hawaii State Supreme Court were Governor Burns' apointees by that time. The appointment also came at a time when protests were ongoing in Kalama Valley where the Bishop Estate was evicting farmers in favor of a residential development. Several dozen Hawaiians picketed the Bishop Estate headquarters and the Hawaii Supreme Court against the Takabuki appointment. Later, on July 17, 1971, more than 1,000 Hawaiians marched through Waikiki in protest of the appointment of Takabuki. In the end, Takabuki gained the appointment and the bells of Kawaihao Church tolled in disappointment. The events pushed the growth of the nascent Hawaiian sovereignty movement.
Takabuki took active management of the Trusts' assets. His investment strategies led to a partnership with Goldman Sachs. In a Honolulu Star-Bulletin article, dated February 7, 2001, Rick Daysog reported on the Goldman Sachs investment:
- Established in 1884 to educate children of native Hawaiian ancestry, Kamehameha Schools initially invested $500 million in Goldman starting in 1992 under the direction of then-trustee Matsuo Takabuki.
- Since Goldman's initial public offering in May 1999, the estate has earned more than $1.7 billion from the sale of stock issued by the investment banking firm. The estate has also earned about $900 million in partnership distributions prior to Goldman Sach's public offering. 
Takabuki was a delegate to Democratic National Convention from Hawaii Territory, 1956.
- Takabuki, Matsuo. An Unlikely Revolutionary: Matsuo Takabuki and the Making of Modern Hawai'i. University of Hawaii Press (September 1998). ISBN: 0824820835.
- King, Samuel P. and Roth, Randall, Broken Trust: Greed, Mismanagement, And Political Manipulation at America's Largest Charitable Trust. University of Hawaii Press (March 2006). ISBN: 082483044X.
- Daysog, Rick. From plantation to power: Matsuo Takabuki and Hawaii -- Tracking the former Bishop Estate trustee's life is an exercise rich in history Honolulu Star-Bulletin, September 9, 1998.
- Daysog, Rick. Takabuki helped make Bishop Estate wealthy Honolulu Star-Bulletin, October 4, 1999.