When you reply to an email you typically have the option, through your email program, to include the email thread with each reply. The email thread is the exchange of emails between you and the person you are replying to. If you don’t have this turned on, please turn it on.
I don’t know about you, but I rely on this email thread. With clients it helps me to see what we’ve been discussing, with editors the email thread can include each step of a discussion or negotiation, and with queries it helps me to see exactly what you’re sending, that I really did request it, and whether or not I want to read it right this minute or if it’s something that can wait until next month. If there’s no thread it typically waits until next month.
Please always include the email thread in your replies to everyone.