[3] His father died whilst he was still at school so he took a job with Lake House (now known as Associated Newspapers of Ceylon Limited) to support his family.

He rose through the ranks becoming the editor of Silumina in the 1950s, Janatha (a Sinhalese daily tabloid), Jana (an international news magazine) and eventually The Ceylon Observer in 1961, a position he retained for nine years.

[4] Peiris left Sri Lanka in the early 1970s to work as the Indian correspondent for a Hong Kong–based newspaper, The Asian.

He then joined the Far Eastern Economic Review working as its regional editor before moving in 1979 to the United Kingdom to become the founder editor of South, a monthly magazine which focused events happening primarily in the underdeveloped Southern regions of the globe - Asia, Africa and Southern America.

Peiris died in London on 6 March 1985,[5] was cremated there, with some of his ashes buried at Highgate Cemetery and the remainder interred in Colombo.