In 2018 and 2019, he exhibited his project KiberaStories in Paris, Kampala, Lisbon and New York. He also participated in the 16th International Dialogue on Population and Sustainable Development in Berlin (October 2018), presenting his collection of photographs, “Women of Kibera”, taken as part of the EU-funded #RightByHer campaign, which works across Africa to make women’s rights a reality.

He was among the 12 visual storytellers selected in 2016 for the World Press Photo East Africa Masterclass in Nairobi, and in 2019, he was selected to attend the New York Times Portfolio Review. Since 2017, he has contributed to Everyday Africa – a collective of photographers sharing images from across the continent to undermine stereotypes and clichés. A professional photographer since 2016, he has balanced his documentary work with assignments for international publications and development organisations. He works regularly as a freelance photojournalist and has contributed visual stories to media outlets, including The New York Times, The Guardian, National Geographic, Der Spiegel, and Rest of World.

KiberaStories won the inaugural East African Photography Award in Kampala in October 2018. He was also awarded in the Feature Stories category at the Kenya Press Photo Awards in 2017 and the Daily Life and Portraiture categories at the Kenya Photography Awards in 2018. In 2019, Brian Otieno was selected as a recipient of the Reuters Photojournalism Grant.