Commercial operation beginning to secure confessions (10)
I believe the answer is:
admissions
'confessions' is the definition.
'commercial operation beginning to secure' is the wordplay.
'commercial' becomes 'ad'.
'operation' becomes 'mission' (mission is a kind of operation**).
'beginning to' says to take the initial letters.
The initial letter of 'secure' is 's'.
'ad'+'mission'+'s'='ADMISSIONS'
(Other definitions for admissions that I've seen before include "Costs of entering" , "Acknowledgments" .)