[1] As a captain posted to the Chitral region of Pakistan, Streather was the official government representative in a Norwegian expedition that made the first ascent in 1951 of Tirich Mir (7,710 m), the highest mountain of the Hindu Kush.

[7] On his return to Britain he was invited to join the Alpine Club (he later became its president from 1990–93), and was selected for trials for the 1953 British Mount Everest expedition.

Though again originally in charge of logistics, he climbed as high as anyone else and was involved in the dramatic events at 7,800 m.[8] In 1955, Streather participated in the 1955 British Kangchenjunga expedition, the third highest mountain in the world.

[12] Streather married his wife Sue (nee Mary Huggan) in April 1956, and they had a daughter and three sons.

Sir Chris Bonington spoke at Streather's memorial service in Hindon Parish Church, and his ashes were interred in the churchyard.