Applying to all and everyone, to all parts or categories with no exceptions

"The reason we have been in such an enormous economic crisis was prompted by reckless behavior across the board” (Barack Obama : presidential debate, October 3rd, 2012)

"Il motivo per cui ci troviamo in una crisi economica tanto grave è stato causato da comportamenti sconsiderati su tutta la linea"

The company is doing extremely well and an across-the-board pay raise is in the cards

L'azienda sta andando incredibilmente bene e un aumento di stipendio per tutti quanti è nell'aria

The US president-elect won the elections when he promised an across-the-board tax cut

Il presidente eletto americano ha vinto le elezioni quando ha promesso di ridurre le tasse a tutti quanti indistintamente

This is an expression used in horse racing. The “board” is the notice-board on which the races and betting odds are listed. Gamblers can bid the same amount of money on the same horse to cover all possible ways of winning money: win (first), place (second), or show (third), or bet across the board on all three possibilities.