Alam's work has been shown at leading museums and galleries in the world, such as the Museum of Modern Art (MOMA) in New York, The Georges Pompidou Centre in Paris, The Tehran Museum of Contemporary Arts, the National Art Gallery in Malaysia and the Tate Modern in Britain.
He started photography in 1980 and was awarded the Harvey Harris Trophy for being judged the best photographer of the year by the London Arts Council in 1983. He became the president of the Bangladesh Photographic Society where he served for three terms].
In 1989, he set up Drik picture library and in 1998, Pathshala: South Asian Institute of Photography. He is also a director of Chobi Mela, the festival of photography in Asia. Jury member of numerous competitions including World Press Photo where he has been a judge on four occasions, he was the first person of colour to chair the international jury in World Press Photo history.
Alam was the first Asian recipient of the prestigious Mother Jones Award for Documentary Photography. His numerous other awards include the Andrea Frank Foundation Award and the Howard Chapnick Award. He has also been awarded the Honorary Fellowships of the Bangladesh Photographic Society and later, the Royal Photographic Society in 2001, for his contribution to photography.
He is on the advisory board for the W. Eugene Smith Memorial Fund and the National Geographic Society. He is visiting professor of Sunderland University in the UK and Regent's Lecturer] at UCLA in the USA. He is an acclaimed public speaker and has lectured at Harvard and Stanford Universities in the USA, in Oxford and Cambridge Universities in the UK, and in numerous prestigious academic institutions in Africa, Asia, Australia and Latin America. Alam is the founder chairman of Majority World, a global community interest initiative formed to provide a platform for indigenous photographers, photographic agencies and image collections from the majority world to gain access to global image markets.
On June 16, 2009 he was detained by the Indian Border Security Force while working on a project based on the river Brahmaputra at the Bangladesh side of the Rowmari-Sahapara border at the district of Jamalpur  but was released after an international campaign was taken up for his release.
Alam set up the South Asian Media Academy. His recent exhibition "Crossfire" curated by Peruvian curator Jorge Villacorta has been widely acclaimed, but was closed down by the police leading to nationwide protests.  The police barricade was removed after Drik’s lawyers served legal notice on the government. The court’s response and subsequent events enabled Drik to open the exhibition for public viewing on March 31.
Alam was a curator of the show "Where Three Dreams Cross" at Whitechapel Gallery in London. The show subsequently went to the Fotomuseum Winterthur in Switzerland. A discussion on Alam's show "Crossfire" took place at the Tate Modern in London on 18 September 2010. The exhibition was later shown at the Queen's Museum of Art in New York, Powerhouse Museum in Brisbane and the Kochi Muziris Biennale. It is currently being shown all across Bangladesh in collaboration with Bangladeshi human rights organisations.
His book "My journey as a witness" was published by the Italian fine art publisher Skira and the Bengal Foundation. It was launched in Dhaka on 23 September 2011. Introductions to the book have been written by Sebastiao Salgado and Raghu Rai. His new book and film "Birth Pangs of a Nation", based on the archives of Drik on the war of liberation of Bangladesh in 1971, was part of the official gifts given by the Bangladesh government to international delegates during the independence day celebrations in 2012. John Godfrey Morris, the legendary picture editor of Life Magazine has called the book, which was listed in the "Best photo books of 2011" by American Photo Magazine, "The most important book every written by a photographer". In 2011, Alam also brought out the book "The Birth Pangs of a Nation", on the refugee situation during Bangladesh's War of Liberation in 1971, which he edited. The book received the Asia Publishing Award for "Birth Pangs of a Nation" in the "Best Insights into Asian Societies (Non-Fiction) Category" in 2012.
Alam is also a pioneer in digital technology in Bangladesh and introduced email to the country in the early nineties. He was recently part of the international jury in the World Blogging Contest (BOBs) held in Berlin.
A 2011 recipient of the Audience Engagement Grant of the Open Society Institute. Alam is currently involved in a nationwide campaign to challenge the process of extra judicial killings.
Alam's most recent work "Searching for Kalpana Chakma" implicates the Bangladesh military in the abduction of Chakma activist Kalpana Chakma who was the president of the Hill Women's Federation. According to her family, Kalpana was abducted by the military on the night of 12 June 1996. The principal accused Major Ferdous has still not been questioned by the police. A film based upon the show was premiered in Bangkok in August 2013. The show will be exhibited in the UK in October 2013.
- Interview with Shahidul Alam By Sabhanaz Rashid Diya and Ahmed Ashiful Haque Niloy (2008)
- Description on Archived FotoFreo 2006 webpage
-  The Lens of 'Majority World' Photojournalism
-  New Age Bangladesh - Shahidul Alam released 6 hours after detention by BSF
-  Media Helping Media - Photojournalist detained on Indian border
-  Podcast in Bangla of Interview of Shahidul Alam in The Daily Star