1
general::
Phrase(s): hand in glove (with someone)
Fig. very close to someone. • John is really hand in glove with Sally. • The teacher and the principal work hand in glove.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
On intimate terms, in close association, as in The internist is hand in glove with the surgeon, so you'd better get a second opinion. This metaphoric expression for a close fit was already included in John Ray's 1678 collection of proverbs, when it was put hand and glove.
American Heritage Idioms