Membership Gateways

I've already successfully set up a gateway for single payments on my site.

I would now like to offer a monthly subscription.

Can't get my head around the relationship between your gateways and paypal when it comes to recurring payments.

Is it that case that users would need to have a Paypal account for this to happen - or does the gateway do something clever.

At the moment I have a so called 'free' business paypal account

Thanks, Ben