Traditional etiquette states that the placment of your host's address be placed upon the back flap of the outer envelope.  This is the sender's address only with no person to be stated.  This can be hand written by the person addressing the envelopes (we recommend a nice brush-like pen that allows minimal ink movement and smudging after writing)  or can easily be added to the envelopes by the printing company for an extra charge.  Sweet Pea Studios, llc tries to balance the affordability of this time saving option at about $.60 per invitation or for a second option which is even more affordable but should be used only with a more casual wedding invitation experience - a personalized rubber stamp that you can order and use to stamp on the envelope back at a flat rate of  $25.00.