How to choose the q-points ?

(From Patrick Tepesh, on 13/9/1999)
Can you give me some hints or refer me to a paper to help me choose q-points for integrating to obtain free energies?
My first impulse is to just use the same MP grids as for the electronic structure calculations,
but it seems from looking at a few papers that this might not be the way most people do it (the papers I've seen so far do not give much detail about the choice of the grid). 

(From Masayoshi Mikami, on 27/9/1999)
Which is the smartest way to choose the q-points for finer mesh in Hexagonal (or Trigonal) Lattice case ? (Is it the same way in the choice of "kpt" in SCF-calculation (MP-mesh)?)

(Response)
About the q-points : usually, one needs in any case the gamma point (for effective charges and dielectric constant).
This point is not part of the usual Monkhorst-Pack (shifted) grids. Unlike with the k-points for the electronic structure calculations,
the workload of each q-point can be very different : if there are remaining symmetries, they can be used fully : the code automatically select the "primitive" perturbations, and do not care about their symmetric. The code even decreases the number of k points if there is still some residual symmetry to be taken into account for one perturbation. Even if unshifted MP grids usually lead to more q-points than shifted grids, each of these q point may be more symmetric, and thus much faster to compute.
The current attitude (see the work in Ferroelectrics 206-207, pp. 205-217 (1998), especially p. 207) is to use a set of MP grids who share common q-points, so that one can judge of the convergence by simple "data reuse"...