  We introduce the dendroidal analogs of the notions of complete Segal space
and of Segal category, and construct two appropriate model categories for which
each of these notions corresponds to the property of being fibrant. We prove
that these two model categories are Quillen equivalent to each other, and to
the monoidal model category for infinity-operads which we constructed in an
earlier paper. By slicing over the monoidal unit objects in these model
categories, we derive as immediate corollaries the known comparison results
between Joyal's quasi-categories, Rezk's complete Segal spaces, and Segal
categories.
