If you know you are going to be setting multiple language versions of a document, an Annual Report perhaps, and you have to have the same page count perhaps because they are going to print back to back as a bi-lingual document, then figure out which language runs the longest first.
For example Irish runs approximately 15% longer than English. Knowing that I can build in 15% extra space in my style sheets when designing the English version. Then when it comes to making the longer language fit I can simply trim the leading, space after etc. on the style sheets until it fits. Because I took this into consideration earlier the longer language shouldn't look too tightly fit.
