Template question - Display code only on first display of template

[Michael Morris]

Is there a way to put a conditional in a template so that area within the conditional only displays on the first occurance of the template.

Example:

<if condition="">
This code is only sent to the document the first time this template is called.
</if>
This code is sent every time the template is called

I'm wanting to write a template that has some inline CSS definition (that I want to be able to smoothly change when the template is inherited), but that CSS need only appear on the template's first instance.