This is an updated version of Cartel by the game's original designer, Philip Orbanes. In the late 70's Phil had added a game of random event cards to Cartel to add variety to the game. In Dallas, those cards are added, the board is also slightly changed in the new theme, which is based on the Dallas TV show.
Players take turns bidding on and buying companies on the board. Larger networks of adjacent companies create higher payouts. Players can also risk taking on debt to pay higher prices, hoping the resulting network pays for the liability of the debt. A deck of random event cards adds a random element, "Dallas Press Events," to each turn (making the game different from the original Cartel).
The winner is the player that acquires the highest net worth, adding together current cash plus the value of their network of companies, less the cost of repaying their debt.
While the game has a theme based on the popular TV shows, only the companies, e.g., Ewing Oil, appear in the game. A very few of the characters are mentioned in flavor text that appears in the rulebook. None of the stars of the show are pictured and the graphic design does not pick up on the TV shows look and feel either.