A few resources if you're looking for information about relatives who worked in one of the Swire companies (Taikoo, Butterfield & Swire, etc):
Rob Jennings, Manager of Archives and Public Affairs at John Swire & Sons Ltd. may be able to help. Here's an example he told recently on the Swire Mariners Association Visitors Book:
A few weeks back I was contacted by an American gentleman asking me if I could help him with information on a B&S man he believed to be his grandfather but who’d changed his name when entering the US in 1905. I was delighted to be able to confirm that the man did work for B&S, the departments he’d worked in and even the reason he’d changed his name (he’d been a very, very, naughty boy). I was even able to send him a copy of a picture of his grandfather as a 24yr old inside the B&S building in Hong Kong. My chap was thrilled at finally having answers to the mystery. The fact that his grandfather hadn’t enjoyed an illustrious career with us was totally irrelevant.
You can contact Rob on his direct Line: 020 7963 9470 (UK number), or by email at email@example.com.
NB For any more general research, Rob recommends contacting the library at The School of Oriental and African Studies in London. They have many of Swire's old files and are much better placed to help the serious researcher.
Visit the G. Warren Swire Collection, which has several hundred photographs of Butterfield & Swire's subsidiaries in China, including Hong Kong. The photographs were taken during 1906-1940.
The Swire Mariners Association website is for "old hands from China Navigation Co. Ltd. and Swire Pacific Offshore". They have a lively visitors book on their website, and also have a group on Facebook.
2016 Update: Swire archives in Hong Kong
I'm pleased to learn from Matthew Edmonson that Swire now run archives here in Hong Kong. He writes:
Swire HK Archive Service was established in 2011 to work together with Swire operating companies in Hong Kong and Asia to professionally manage their historical archives.
Swire’s principal operating companies are represented in the archives, which includes our head office in Hong Kong, John Swire & Sons (H.K.) and Swire Pacific, and the group companies of Swire Properties, Cathay Pacific Airways and HAECO; the collections reflect Swire’s heritage in shipping, aviation, beverages, trade, and property.
Researchers with an interest in Swire history may contact us to make an appointment to consult the archives, or may send their enquiries regarding our services to: firstname.lastname@example.org
If you know of any other good resources, please leave a comment below.