Information on (La)TeX packages

amssymb

amssymb breaks if used together with stmaryrd (\circledS command is defined by both). This particular command is also defined by mathdesign. To overcome this, before loading amssymb, do \let\circledS\undefined.

bm

Creates bold math symbols, though don’t use with Latin letters, for in math mode, \bm{} will leave it with an italic slant, which is usually not what one wants.

If used, package bm must come after package amssymb; otherwise Error: Too many symbol fonts declared ensues.

To avoid other surprises—e.g., screwing up \mathbf{}—it is best to also place it after mathdesign, fontspec, and amsmath.

mathdesign

Sets up a math font (I usually use with bitstream-charter). To avoid surprises, make sure it is loaded before fontspec, and bm.