I see that quite a few people find their way here hoping for an answer to the question "what does RSP mean?" If this describes you then perhaps I can help.

The acronym RSP stands for many things, including:

These terms are all predominantly American in their useage, especially the educational meaning, which in Britain is usually known as "Special Educational Needs" or SEN.

In my own case RSP simply stands for Robin Stephen Prior - my name.

For an exhaustive explanation visit the Acronym Finder, which says that there are at least 47 meanings for RSP (in English), including the Revolutionary Socialist Party of India, and the Roscoe, Snyder, & Pacific Railway Company. And if we allow things like the Romanian Society for Physics and the Red Spectacled Parrot, there are many more - although as far as I can see none of them has anything to do with replying to formal invitations.

While I'm at it, there are a few different Robin Priors too.

The Australian military historian is here

The South African businessman is here

The San Francisco computer engineer is here

The British educational psychologist and writer on NLP doesn't seem to have a website.

As Stephen Fry might say, if you have been, I thank you.