“Take/Taking care of business” is an old term that dates to at least the 1900s. The rock group Bachman-Turner-Overdrive (BTO) popularized the saying with their 1973 hit song, “Takin’ Care of Business.” The Office Depot has used the BTO song in its commercials.
 
Several songs between 1959 and 1962 were titled ‘Taking Care of Business” or ‘Takin’ Care of Business.” Jazz musicians used the initials “TCB” by at least 1960. Elvis Presley called his “Memphis Mafia” (friends and employees) “TCB” and, in 1975, had the “TCB” initials painted on his private plane.
   
     
Wikipedia: Takin’ Care of Business
“Takin’ Care of Business” is a song written by Randy Bachman and first recorded by Canadian rock group Bachman–Turner Overdrive (BTO) for their 1973 album Bachman–Turner Overdrive II.
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Pop Culture
. The song has been used as an advertising campaign for companies such as Office Depot, whose business target consists largely of small business owners.
 
Wikipedia: Taking Care of Business
Taking Care of Business is a film comedy made in 1990 starring James Belushi and Charles Grodin. It was directed by Arthur Hiller.
     
Wikipedia: TCB Band
The TCB Band was a group of professional musicians who formed the core rhythm section of Elvis Presley’s band from August 1969 until his death in 1977. TCB stands for Taking Care of Business, a personal motto Presley created in the early 1970s.
 
Wikipedia: Memphis Mafia
The “Memphis Mafia” was the nickname for a group of friends, associates, employees and “yes-men” whose main function was to be around Elvis Presley from 1954 until he died. Several filled practical roles in the singer’s life. For instance, they were employed to work for him as bodyguards or on tour logistics and scheduling. In these cases Elvis paid salaries, but most lived off fringe benefits such as gifts, cars, houses and bonuses. Over the years, the number of members grew and changed, but for the most part there was a core group who spent a lot of time with the singer.
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The acronym TCB
Presley and his friends and employees also adopted the acronym TCB which meant “Taking Care of Business”. Presley had the tail of his private jet painted with the initials “TCB” and a lightning bolt and gave away TCB & TLC on gold chain necklaces as gifts.
     
Google Books
10 August 1959, Billboard magazine, pg. 34, col. 3:
SCOTTIE (Jazz—ed.)
The Shirley Scott Trio.
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Many of the tunes are originals, such as “Hong Pong” and “Takin’ Care of Business,” and there are standards such as “Mr. Wonderful” and “Cherry.”
 
OCLC WorldCat record
We told you not to marry ; Taking care of business
Author: Titus Turner
Publisher: New York, N.Y. : Glover Records, [1959?]
Edition/Format:  Music : 45 rpm : Popular music : English
 
7 February 1960, New Orleans (LA) Times-Picayune, “Hurrah and Ho-Hum for Red-Blood Slang,” Art Buchwald Reports, sec. 2, pg. 7, col. 3:
KILBERT TOOK OVER.
“Ake, what is TCB?”
 
Persson thought hard. “Taking care of business?”
 
“Correct,” Miss Gray said. “Whatever you’re doing seriously is TCB.”
   
OCLC WorldCat record
Taking care of business ; Honey boy
Author: Ruth Brown; Howard Biggs, musician.
Publisher: [New York, N.Y.] : Atlantic, [1960?]
Edition/Format:  Music : 45 rpm : Blues : Multiple forms : Popular music : English
     
Google Books
26 September 1960, Billboard magazine, pg. 8, col. 1 ad:
RUTH BROWN
TAKING CARE OF BUSINESS
 
OCLC WorldCat record
Takin’ care of business
Author: Gene Russell Trio.
Publisher: Los Angeles : Dot, [196-?]
Edition/Format:  Music LP : Jazz : No Linguistic Content
 
27 February 1961, Redlands (CA) Daily Facts, “Postcard From Los Angeles: And All That Jazz” by Stanton Delaplane, pg. 12, col. 8:
“The problem for the jazz musician,” said Mr. Art Farmer, “is not making up jazz language. It is learning it from the fans. Half the time we can’t understand what they are saying to us.”
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“Well, man,” said Mr. Farmer. “We’re professional musicians. We just try to TCB.”
 
“What is that? Mr. Farmer?”
 
“Take care of business,” he said. “You know. Be conscientious.”
   
OCLC WorldCat record
Takin’ care of business ; The stumble
Author: Freddy King
Publisher: [S.l.] : Federal, [1961?]
Edition/Format:  Music : 45 rpm : Blues : Multiple forms : Popular music : Rock music : English
   
OCLC WorldCat record
Takin’ care of business
Author: Ral Donner; Alan Lorber; Artie Ripp; Jan Hutchins
Publisher: New York, N.Y. : Gone, [1961?]
Edition/Format:  Music LP : Popular music : English
   
Google Books
13 January 1962, Billboard magazine, pg. 1, col. 1:
TAKIN’ CARE OF BUSINESS. Ral Donner, Cone
 
Google Books
8 December 1962, Billboard magazine. pg. 28, col. 5:
DON GARDINER AND DEE DEE FORD
T.C.B. (Taking Care of Business)
   
Google Books
Blues for Mister Charlie: a drama in three acts
By James Baldwin
New York, NY: Samuel French
1964
Pg. 43:
RICHARD. (laughs) Let’s TCB — that means taking care of business.
   
OCLC WorldCat record
Taking care of business
Author: Larry Page
Publisher: New York : Calla, [1967?]
Edition/Format:  Music LP : Popular music : No Linguistic Content
 
Google Books
Black Arts;
An anthology of Black creations
Edited by Ahmed Akinwole Alhamisi and Harun Kofi Wangara
Detroit, MI: Black Arts Publications
1969
Pg. 29:
Joe Goncalves. lf one would speak with the seemingly endless number of young nationalist intellectuals anywhere in the country about Black culture, one would be reassured that we’re “TCB” (takin’ care of business) in that area, and that things are getting better and better, “‘cause we’re really showing whitey that we don’t need his western thing.”
 
OCLC WorldCat record
Taking care of business
Author: James Cotton Blues Band.
Publisher: Hollywood, Calif. : Captiol Records, [1971]
Edition/Format:  Music LP : Blues : English
 
Google News Archive
16 November 1975, Tuscaloosa (AL) News, pg. 7C, col. 3:
Elvis gets
new plane
MEMPHIS (AP)—The latest addition to Elvis Presley’s airplane fleet has arrived at Memphis International Airport where it has already begun attracting attention.
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TCB, the initials of Presley’s company, Taking Care of Business, are painted on the plane’s high tail.