I am using LaTeX and in some cases have multiline footnotes.
When I use a two-column format and especially when the reference to a footnote is low in the column, LaTeX will often split the footnote in half: it starts in the original column, but then continues under another column (sometimes in another page), which is very distracting.
Is there a way to force LaTeX to never split footnotes and allocate enough space for them?
I've found that it's best to get the style sheet from where you're trying to publish, and just use their format (I'm assuming you're trying to publish somewhere, if you're using a double-column format). The editors can then handle wacky footnoting. If it's for a thesis, I don't know about your committee, but mine has told me that a single column, double-spaced is the way to go, which should avoid your problem in the first place.
Use \interfootnotelinepenalty=10000 to totally disallow this. But be prepared for other layout artifacts... Setting the penalty lower than 10000 will give TeX some flexibility in deciding when the side effects are too bad to bear.
For a detailed discussion see http://www.tex.ac.uk/cgi-bin/texfaq2html?label=splitfoot