The most common and most likely answer to this crossword clue is the 15 letter word REPRESENTATIVES
I've seen this crossword clue in Independent
R
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More clues leading to the result REPRESENTATIVES
- Vast enterprise deviously penetrated by English agents
- Vast enterprise collapses without English salespeople
- Delegates preserve state in disarray
- MPs perhaps disturbed by inveterate press
- Unorthodox priests venerate archetypes
- They should flog politicians?
- Traveller’s gift is left with relatives
- Ambassadors monstrous priest venerates
- Delegation treacherous, titan perseveres
- Delegates of a vet’s enterprise at sixes and sevens
Buddy explains!

The straight part
We know that "salespeople" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case salespeople = representatives.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does REPRESENTATIVES mean?
REPRESENTATIVES noun- A delegate.
- Something standing for something else.