A Taken In Hand (TIH) relationship is a consensual male-led exclusive monogamous relationship in which the man's control is real and for the purpose of creating a deeply connected, fully engaged relationship with a strong sexual connection. The term has been popularized by the UK Web site of the same name.
How the man expresses his leadership and control is an individual matter, but it is for the benefit of the relationship rather than being purely self-serving. The Taken In Hand man protects and cherishes the woman he leads. The Taken In Hand woman responds positively to her man's authority and leadership. It is not necessarily a Domestic Discipline relationship, though it can be.
Taken In Hand couples often think of themselves as vanilla (though many may not know the word in this context) and tend to be unfamiliar with or turned-off by BDSM or its literature, often cited is the exotic language, customs and rituals.
Taken In Hand is not often about the woman being slavishly obedient or submissive by default. It is more likely to be about the man correcting and controlling her to the delight of both. In some D/s relationships, the woman might aspire to be more submissive, whereas in many a Taken In Hand relationship, the woman will have no such aspiration.