Step 1: Note the coordinates.
Point $P(x_1, y_1) = (-2, 5)$ and Point $Q(x_2, y_2) = (5, -2)$.
Step 2: Recall the Distance Formula.
\[ PQ = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} \]
Step 3: Compute the differences.
$x_2 - x_1 = 5 - (-2) = 7$ and $y_2 - y_1 = -2 - 5 = -7$.
Step 4: Square and add the differences.
\[ (7)^2 + (-7)^2 = 49 + 49 = 98 \]
Step 5: Take the square root.
\[ PQ = \sqrt{98} = \sqrt{49 \times 2} = 7\sqrt{2} \]
Step 6: Conclusion.
The distance between points $P$ and $Q$ is $7\sqrt{2}$ units.
\[ \boxed{7\sqrt{2}} \]