user12: The wikipedia article is a good starting point, but I'm also interested in how the specific regulations have changed over the years.
Currently, 3 norms must be achieved1 in tournaments that adhere to specific guidelines including foreign players, titled players, and a certain performance rating must be attained.  
What was the origin of the current rules, and what were the earlier rules?

1. Usually...  there are exceptions to this however.

user70: One way it is evolving is with the informal 'super-GM' title.  At one time, there weren't many GMs.  Being a GM was being in an elite club.  Now there are a lot of GMs and the differences in their strengths are beginning to show.  (I'm not talking about a GM's performance degrading due to age...)
From the wiki linked below:

In 1972 there were only 88 GMs with 33 representing the USSR. The
  current FIDE ratings list includes over 1000 grandmasters.

Perhaps 20 years ago, a GM rated 2600 was a 'super GM'.  Now 2700 could well be that mark, with some GMs peaking at 2850 or so.
Also from the article:

December 2008 saw a record number of GMs (1,192) and IMs (2,916)
  causing some FIDE officials to suggest that FIDE should consider an
  "elite grandmaster" title.[17] The unofficial title, "Super
  Grandmaster", is often used by players to refer to those with a 2700+
  rating to distinguish the most serious world champion contenders.

Read more here.  This article also includes a synopsis of how GM and IM norms are earned, including rules changes by year.  It's very interesting.

12: <p>The <a href="http://en.wikipedia.org/wiki/Grandmaster_%28chess%29">wikipedia article</a> is a good starting point, but I'm also interested in how the specific regulations have changed over the years.</p>

<p>Currently, 3 norms must be achieved<sup>1</sup> in tournaments that adhere to specific guidelines including foreign players, titled players, and a certain performance rating must be attained.  </p>

<p>What was the origin of the current rules, and what were the earlier rules?</p>

<p><hr />
1. Usually...  there are exceptions to this however.</p>
 70: <p>One way it is evolving is with the informal 'super-GM' title.  At one time, there weren't many GMs.  Being a GM was being in an elite club.  Now there are a lot of GMs and the differences in their strengths are beginning to show.  (I'm not talking about a GM's performance degrading due to age...)</p>

<p>From the wiki linked below:</p>

<blockquote>
  <p>In 1972 there were only 88 GMs with 33 representing the USSR. The
  current FIDE ratings list includes over 1000 grandmasters.</p>
</blockquote>

<p>Perhaps 20 years ago, a GM rated 2600 was a 'super GM'.  Now 2700 could well be that mark, with some GMs peaking at 2850 or so.</p>

<p>Also from the article:</p>

<blockquote>
  <p>December 2008 saw a record number of GMs (1,192) and IMs (2,916)
  causing some FIDE officials to suggest that FIDE should consider an
  "elite grandmaster" title.[17] The unofficial title, "Super
  Grandmaster", is often used by players to refer to those with a 2700+
  rating to distinguish the most serious world champion contenders.</p>
</blockquote>

<p><a href="http://en.wikipedia.org/wiki/Grandmaster_%28chess%29">Read more here</a>.  This article also includes a synopsis of how GM and IM norms are earned, including rules changes by year.  It's very interesting.</p>
