John Stanley Donaldson was born in 1936 in Tobago. He attended Rosary Boys and Tranquility College before going to Osmond High School and St. Mary's College where he was also a teacher. Donaldson went on to attend Johns Hopkins University where he specialised in International Studies. He also attended University of British Columbia (Canada) where he achieved degrees in Economics and Law. He attended Law School.

Donaldson joined the Foreign Service held a number of diplomatic post including stints in London, Nigeria and one in Washington under then Ambassador Ellis Clerke. He followed in his father's footstep into politics as his father John Snr. was a member of the Legislative Coucil. Donaldson won the St. Anns West seat for the PNM and was former Minister of Labour, Social Security and Co-operatives. He has served the longest tenure as Minister of National Security and Minister of External Affairs thus far (9 years) during the period September 1976 - September 1985