Vigilant is a science fiction novel written by the Canadian author James Alan Gardner, published in 1999 by HarperCollins Publishers under its various imprints.HarperCollins, Avon, SFBC/Avon-Eos; paperback edition 1999, Eos Books. The book is the third volume in Gardner's League of Peoples series, after Expendable (1997) and Commitment Hour (1998).The series continues through Hunted (2000), Ascending (2001), Trapped (2002), and Radiant (2004).

'Vigilant' was the victorious United States defender of the eighth America's Cup in 1893 against British challenger Valkyrie II. Vigilant was designed by Nathanael Greene Herreshoff and built in 1893 by the Herreshoff Manufacturing Company of Bristol, RI. It was Herreshoff's first victorious America's Cup defender design.

Attentive to discover and avoid danger, or to provide for safety; wakeful; watchful; circumspect; wary.

carefully observant or attentive; on the lookout for possible danger; "a policy of open-eyed awareness"; "the vigilant eye of the town watch"; "there was a watchful dignity in the room"; "a watchful parent with a toddler in tow"