It's always good to have a book to follow when teaching/learning Italian. But this book is absolutely not written by any native speaker. In some points I would believe it has been written using an automatic translator.
For example: # It's «Agenzia di viaggi», not «Agenzia di viaggio» (Lezione 2) # It's «Aeroporto», not «Aereoporto» (pages 20-21) (this is a huge mistake in Italian) # And please! In Italian we don't put the 'lei' with a capital letter. You may only find this is a extremely formal (and bad written) letter.
Really Berlitz, did you hire a (non Italian) monkey to put this book together?