# If X is a Haussdorf topological space and R and equivalence relation on X, when is X/R Haussdorf?

I was wondering if there are some necessary and sufficient conditions for the quotient space to be Haussdorf. I have been trying a little for a while, but I only got very restrictive sufficient conditions.

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The correct spelling is "Hausdorff". –  Angelo Mar 10 '13 at 16:59
You should look in Bourbaki. They have a lot on this. For a compact Hausdorff space X if R is closed in XxX then X/R is closed. –  Benjamin Steinberg Mar 10 '13 at 22:48

If $X$ is Hausdorff and the quotient map $X\to X/R$ is open, then $X/R$ is Hausdorff if and only if $R\subseteq X\times X$ is closed (see http://math.stackexchange.com/questions/91639/x-sim-is-hausdorff-if-and-only-if-sim-is-closed-in-x-times-x).