What is the single most important concept in pilot-controller radio communications?

4-2-1. General
a. Radio communications are a critical link in the ATC system. The link can be a strong bond between pilot
and controller or it can be broken with surprising speed and disastrous results. Discussion herein provides basic
procedures for new pilots and also highlights safe operating concepts for all pilots.
b. The single, most important thought in pilot-controller communications is understanding. It is essential,
therefore, that pilots acknowledge each radio communication with ATC by using the appropriate aircraft call
sign. Brevity is important, and contacts should be kept as brief as possible, but controllers must know what you
want to do before they can properly carry out their control duties. And you, the pilot, must know exactly what
the controller wants you to do. Since concise phraseology may not always be adequate, use whatever words are
necessary to get your message across. Pilots are to maintain vigilance in monitoring air traffic control radio
communications frequencies for potential traffic conflicts with their aircraft especially when operating on an
active runway and/or when conducting a final approach to landing.
c. All pilots will find the Pilot/Controller Glossary very helpful in learning what certain words or phrases
mean. Good phraseology enhances safety and is the mark of a professional pilot. Jargon, chatter, and "CB" slang
have no place in ATC communications. The Pilot/Controller Glossary is the same glossary used in FAA Order
JO 7110.65, Air Traffic Control. We recommend that it be studied and reviewed from time to time to sharpen
your communication skills.