His fascination with the elegance of sleight-of-hand and what Slaight himself terms "the brilliance of inventions" resulted in a robust job as a performer touring Western Canada as mind reader "Will Powers", and where he performed a large scale magic show under the "Slaight & Co" banner. His travelling magic show would often see him spend 14 hours away from home visiting small towns to perform for $10. Slaight's travelling magician's show was no doubt inspired from his early days in the 1940s performing for his grandfather's staff at a local bank in Galt for $2, or his regular performances at conventions and at the Rotary Club in Moose Jaw. So prominent was magic in young Slaight's life that he toyed with the idea of performing on a permanent basis, and would have done so, Slaight later admitted, had it been profitable.

John Allan Slaight was born in Galt (now Cambridge), Ontario, Canada to Florence Eileen Wright and John Edgar (Jack) Slaight, a newspaperman who worked for the Galt Evening Reporter (now Cambridge Reporter). His family (including Slaight's younger siblings Brian and Ann) moved to Moose Jaw, Saskatchewan when his Father Jack bought the Moose Jaw Times-Herald in 1945. Jack Slaight was also the eventual co-owner of Moose Jaw radio station CHAB-AM, one of Canada's first radio stations.

Slaight began his broadcasting career in Moose Jaw, Saskatchewan in 1948 at age 17 as an on-air news reporter and announcer for his father's station CHAB. His late night jazz program, Spins and Needles, whet his appetite for the radio industry, which, through the next five decades, would become his life. "I had never been inside a radio station before. But after one short visit to CHAB, I realized radio was what I wanted to do with my life," Slaight said in a 2002 interview.

Slaight arrived at the University of Saskatchewan in autumn 1949 to uphold a bargain he made with his Father. In exchange for working the one year at CHAB, Slaight was required to attend university. While at the University of Saskatchewan, Slaight worked as a columnist (A Sap's Fables) and jazz reviewer for the college newspaper, The Sheaf. Slaight dropped out of his studies at the University of Saskatchewan after his first year and balanced his burgeoning broadcasting career with his travelling magic show.

In 1950, Slaight and his wife Ada moved to Edmonton, Alberta. Unable to find a job in radio, Slaight sold shoes at the Eaton's Department store before finally joining radio station CFRN that same year as a news reporter before leaving to join CJCA in 1952.

In 1954 Slaight joined Edmonton-based radio station CHED-AM as the station's News Director. Two years later in 1956, Slaight was appointed Merchandising Director.

In early 1958 Slaight was hired as program and promotions manager for Toronto-based CHUM radio station. CHUM had earlier turned to rock and roll to achieve a larger listenership and it was hoped that importing Slaight from Edmonton would allow CHUM to reach the number one spot on Toronto's radio waves.

By 1960, Slaight had been promoted to become CHUM-AM's Program Director, a position that he held until 1964.

With Terry Bate (of Stephens & Towndrow, a sales promotion company in Canada), Don McKenzie and Saundra MacKenzie, Slaight travelled to England to establish a sales agency for Radio Caroline. Radio Caroline had been founded by Ronan O'Rahilly in 1964 to overcome the BBC's radio broadcasting monopoly. "Unlicensed by any government for most of its early life, it was a pirate radio station that never actually became illegal, although after the Marine Offenses Act it became illegal for a British subject to associate with it." The station operated beyond the 12-mile limit off the English coast broadcasting from International Waters on a ship, and aired rock music and commercials (not broadcast by BBC Radio) into London.

His passion for programming served him well when in 1965, Slaight was appointed to become the Vice President of Radio CHUM-1050 Ltd and elected to the board. Responsible for all programming and operations of CHUM-AM and its sister station CHUM-FM, Slaight remained with CHUM-1050 Ltd until 1966 when he and his family left the country for England.

Slaight returned to Toronto in 1967 with a renewed passion to own his own radio station. Upon his return he formed Allan Slaight Limited, a company engaged in advertising and communications. He then established a strategic partnership with Stephens & Towndrow for his company to act as consultants in Programming, Sales and Marketing. Stephens and Towndrow was a sales firm which placed commercials with radio and TV stations. They represented 18 AM and FM radio stations throughout Canada and had been acquired by Canadian broadcasters from CBS Radio. By September of that same year, Stephens & Towndrow publicly announced that Slaight was to be appointed President and Managing Director.

On December 14, 1970, approval was given for Slaight Broadcasting Ltd. to purchase CFGM Broadcasting Ltd. from owners John Graham and Stewart Coxford. The following year in 1971, Allan Slaight took ownership of CFGM. CFGM, at the time, was Canada's first full-time country and western music station. It wasn't until an application was made in 1976 that CFMJ's frequency was moved to 1320 kHz.

On July 13, 1972, Slaight was granted permission by Canadian Radio-television and Telecommunications Commission (CRTC) to acquire 80 per cent holdings of Montreal-based station CFOX-AM. Upon ownership, Slaight changed the format to "new country music" to match CFGM.

After becoming President of a company running three radio stations and three cable systems, Slaight made a $12 million bid in early 1973 to acquire 52 per cent of Bushnell Broadcasting of Ottawa, Vancouver, and Toronto. The CRTC rejected the bid on March 26, 1973. But, the following day, Slaight was pleased to find out he and the board of Directors had been given permission to acquire the fledging and debt-ridden Global Television Network that had been founded by Al Bruner.

In 1974, Slaight authorized a rights offering of IWC's shares where proceeds would be used to Finance a portion of Global Communications Ltd. Slaight also was granted approval from the network's original public Investors to change voting power and repayment terms so that he could better financially negotiate for the September television line-up.

By December 1976, Slaight had successfully navigated Global out of debt and the television station had reached a break-even point in its day-to-day operations. In an ambitious move, Slaight and IWC exercised a "buy-sell clause" on December 22 to buy out its investment and financing partners Global Communications Ltd. and Seymour Epstein. Collectively, the two partners held 55% of Global's holdings. Instead, Slaight and IWC were bought out by Winnipeg Theatre tycoon Paul Morton.

In 1976 Slaight applied for a CFGM-AM renewal licence and asked the CRTC to consider an FM licence for a sister station. Slaight proposed that the new station would offer an ombudsman Service for listeners and include other services such as consumer reports. The station, operating on bandwidth 107.1 was licensed that summer and Q107 debuted on June 1, 1977 with offices operating from Toronto's Hudson Bay Centre, 30th floor and transmitting from the CN Tower.

In 1978, Allan Slaight made a bid for all the Common shares outside of Radio IWC Ltd. essentially becoming IWC's largest shareholder. At the time, he owned 14 per cent, with Allpak Products Ltd. controlling 36 per cent. Under the new agreement, Slaight acquired another 42 per cent (including 36% from Allpak Products Ltd and 6% from Joseph Mac-Brien), and purchased CFGM Broadcasting Ltd. (CFGM and CILQ-FM) from IWC Communications Ltd. in 1978 following the sale of his interest in the Global Television Network and IWC's cable interests. He renamed Radio IWC Ltd to Slaight Communications Inc. the following year.

In 1982, Slaight bought controlling interest in Urban Outdoors, the second largest outdoor advertising Business in Canada. The company specialized in backlit outdoor advertising in Canada's 20 largest markets. The pairing of outdoor advertising with radio seemed a natural fit to Slaight who stated that the Business was "about as recession-proof as any Business."

In July 1985, Allan Slaight acquired Conrad Black and Montegu Black's Hollinger Argus Ltd.'s 49 per cent stake in Standard Broadcasting Corp.

In that same year, Allan Slaight sold CJOH-TV (Ottawa), an affiliate of CTV so he could focus on expanding his radio holdings for Standard Broadcasting. The decision was prompted by a 1987 CRTC ruling in which the CRTC awarded a new TV licence for the Ottawa area. Both CHUM and Baton Broadcasting eagerly entered the bidding race, which encroached on Slaight's own Ottawa-based CJOH franchise. When Baton pitched "National Capital Television," a patriotic showcase for Canadiana and Canadian content viewing that would spend $31 million over five years on Canadian programming, the CRTC awarded Baton the Ottawa licence. Slaight, angered, appealed to the Federal Cabinet, citing that the "decision ha[d] the potential for changing the face of Canadian broadcasting." But instead of opening a competing Ottawa station, Baton approached Slaight and offered to buy CJOH for a premium price of $85 million. Slaight accepted, and Baton surrendered its awarded licence to the CRTC, having used the licence acquisition as a bartering chip against Slaight.

On April 8, 1988, the CRTC approved the purchase of CJOH by Baton Broadcasting Inc., with the transfer taking place May 5, 1988.

Slaight is the author of a number of magic titles including Stewart James in Print: The First Fifty Years (1989), The James File (3 Book Set) (2000), the largest work ever published on magic, let alone on the magic of one man, and Essential Stewart James (2007). Slaight co-hosts an annual magicians conference, 31 Faces North, with performing arts organization Magicana (Artistic Director David Ben) every summer. It is an annual invitation-only event inspired by and meant to resurrect the spirit of collaboration and camaraderie seen in the once-held magicians event (The Ibidem Event) hosted by P. Howard Lyons.

Allan Slaight was not just involved in broadcasting. In the early 1990s, he partnered with John Bitove Jr. to launch the Toronto Raptors, the first NBA franchise outside of the United States. Slaight, like Bitove Jr. held a 39.5 per cent share with the Bank of Nova Scotia holding 10 per cent, Isiah Thomas (9 per cent) and other minority holding partners. Brought together by former Ontario Premier David Peterson (1 per cent holding), Slaight and Bitove were persuaded that Toronto was a market ready for an NBA franchise. When they pitched the NBA, they included in their presentation plans for a state-of-the-art downtown arena dedicated to the Raptors.

Slaight and Bitove eventually disagreed on this very arena, with Slaight calling it "financial suicide" to build a separate stadium without the Maple Leaf hockey franchise who publicly declared to build their own arena, meaning two rival buildings. The Maple Leafs were willing to share the majority of the cost burden and have the Raptors act as a junior, tenant. Eventually, Slaight invoked the "shotgun clause" in his ownership deal, essentially forcing either Bitove or Slaight to buy out one another with a 60-day limit to pay the cash. Slaight prevailed and reluctantly bought out Bitove, whose passion for the Raptors was evident but declined the offer. On November 15, 1996, Slaight gained 79 per cent control of the Raptors. "It's exciting, nervous-making and at the same time very proud. It's a big financial exposure. Anything of this magnitude would make any sane individual nervous – and I still have some sanity," Slaight said.

Though Leafs Chairman Steve Stavro publicly declared having little interest in moving the Maple Leafs to the proposed new arena, the Air Canada Centre at the foot of Bay Street, Slaight insisted that the "city need[ed] a two-team building." With Slaight contractually obligated to build the NBA arena (lest he pay $75 million in fines), and Stavro in negotiations with Slaight, land for the Air Canada Centre was purchased in November 1996 at Bay Street and Lakeshore Boulevard. Shovels went into the ground February 5, 1997 with an official groundbreaking ceremony held on March 13, 1997, Ultimately the Ontario Teachers Pension Plan led the buyout of Slaight from the Raptors and Air Canada Centre, putting the two teams in one building and insuring the financial viability of Toronto's new home for Sports and entertainment and rebranding the Business as Maple Leaf Sports & Entertainment.

Slaight has a long history of philanthropic activities in a number of health and arts related realms. Slaight's ethic of philanthropy was summarized in an interview conducted in 2001. "I've done pretty well by Canada and by Toronto, and I very strongly believe you should give a lot back."

In 2002, Standard acquired Iceberg Media.com Inc, an internet radio portal providing music for Web sites. The acquisition complemented Standard's existing portfolio as they held a minority interest in Moontaxi (a jazz and classical music online radio service) and MapleCore Ltd. (an e-commerce portal selling concert merchandise and tickets).

In 2003, Standard held a 30% interest in Canada's first licensed "Urban" station, Milestone Radio Inc. and an equivalent interest in Haliburton Broadcasting Group Inc. that consisted of nine Ontario stations, a group of rural Alberta stations and a Calgary-based jazz station, as well as a number of other interests (Sound Source Networks, Video One, Instore Focus Inc, Professional Warehouse Demonstrators, Canada Post Transfer Corporation).

In 2004, Standard Radio joined with CBC/Radio and SIRIUS Satellite Radio to bring satellite radio to Canada.

While Slaight focused his talent for showmanship in the realm of broadcasting, magic continues to be ever present in Slaight's life. In an interview with the Globe and Mail in 2005, Slaight proudly showcased his extensive library of magic trick books. The collection numbers in the thousands of volumes and is one of the single largest collections on the craft.

In 2007, Allan Slaight authorized the sale of Standard Radio Inc. to Astral Media Inc. in a $1.08 billion deal. The negotiation saw Slaight taking one-fifth of the purchase price of Astral stock ($880 million cash), giving Slaight a non-voting stake (4.75 million class A non-voting shares) in the company of 8.7 percent. The sale did not include Standard's interests in Sirius Satellite Radio, Iceberg Media, Flow 93.5FM, Haliburton Broadcasting and Newcap Inc. in Alberta.

Slaight's own magic tricks (the Magnetic Miraskill, OTWONE Prediction and others) can be found in most magic magazines from the past 50 years such as Ibidem, Genii – The Conjurors' Magazine, and Magic – The Independent Magazine for Magicians. Slaight's contributions to the world of magic were acknowledged by Magicana when he was presented with Spins and Needles: The Magic of Allan Slaight, a hardcover book celebrating 62 of Slaight's own magic tricks.