Inviting people to christening

[SnuggyBuggy]

I know I could look on Debretts but I also would like to know what people do in real life.

Getting baby christened in the new year and wonder how people usually handle this. In my family these tend to be big celebrations with lots of people invited.

Do people send invitations with RSVPs these days or just do it over the internet? We will probably self cater so would only need vague numbers. A lot of people we would invite live a long way away and we wouldn't want to pressure anyone.

How do people do christenings these days?