  We determine a family of functors from a poset to abelian groups such that
the higher direct limits vanish on them. This is done by first characterizing
the projective functors. Then a spectral sequence arising from the grading of
the poset is used. Also the dual version for injective functors and higher
inverse limits is included. Graded posets include simplicial complexes,
subdivision categories and simplex-like posets.
