What to do when you invite someone round, how to set the table, how to arrange the seating. 
A few simple rules for you to remember. 

2	Invitation cards

This kind of invitation is sent 10 or 12 days before and a phonecall is not received because it contains the letters s.p.r. which has the same meaning as "r.s.v.p.". 

You should answer at once by phone or by letter whether accepting or declining. If there is no mention of black tie the invited person should arrive in sombre dress.

Example 1

Paolo and Georgia Rossi Saturday, 13th May at 9pm, for “pranzo”   Black tie  p.m. s.p.r.

Black tie means: tight for gentlemen and smart dress for ladies 
The letters p.m. stand for "pro memoria" 

Example 2

Roberto and Emanuela Gigli Are honoured to invite Mr. & Mrs. Beccaceci To come to "pranzo" At 9pm, Thursday 21st May   Tel: 771944  s.p.r.