Re: Act Appropriately Up To the Cxx Level...
When I "act appropriately at the Cxx level" it means a combination of things.
First of all: suit and tie. Imperative. Plus it saves a lot of time. (A modest, tailored, skirt/jacket if you prefer) Instead of having to spend the first 20 minutes of any meeting establishing your credentials, being dressed for the part and having "a firm handshake, a certain look in the eye and an easy smile" means you have at least 30 seconds to tell them something they need to know, before their attention wavers or their phone rings.
Third: listen some more. This is more a sign of showing respect. If you've prepared properly, you will already know what they will say to you.
When you do speak, speak slowly. Use business terms (but never cliches you picked up from buzzword-bingo). Never, ever, make the person you're talking to feel stupid or insecure. Always explain everything - you don't get to be CxO by being stupid, so they pick stuff up quickly if it's in their interests to. So make it in their interests.
Leave your phone behind or switch it off. The chances of the caller being more important that your audience is almost zero.
Finally: know why you have gone into that meeting and know what you are going to ask for after you've made your pitch. The primary goal of the meeting is to tell them something to their advantage. Your goal is to get what you want. If you aren't asking for anything, there's no point being there. When you do ask, don't apply pressure - try to give them as much warning as you can (maybe a comment right at the start) and don't drop any surprises on them.