Is it simply by knowing SQL? You know, all the big forums have converters to the other big forums, and it's like finding which forum has the converter to YOUR forum of choice. I recently found someone who went from SMF to phpbb to bbpress. But how do these things get written in the first place? SQL? And if SQL, are we talking about "for dummies" after say 3 hours of Lynda training, or we are talking about really advanced proficient SQL experience?