"Description is most effective when it is woven into the action, and best when it comes with an emotional charge by being filtered through a character's perceptions. If they are at home in the world, the characters will not spend a lot of time concentrating on the details."--Lisa Tuttle, Writing Fantasy and Science Fiction
Note: A solid book on the field. The unique strength or value of this book is its analyses. Her advice is familiar but when she breaks down her work or those of others, you'll want to listen.