Bridge - Conventions Bridge - blackwood after the intervention.
| Never mind. | Obr. | Odp. | |
| 4NT | X | NOT | 1-4 values |
| XX | 0-3 values | ||
| 5♣ | 2 worthless values | ||
| 5♦ | 2 values + right atu | ||
| 5♥ | 2 values + right atu + 1 King | ||
| 5♠ | 2 values + right atu + 2 queen | ||
| Never mind. | Obr. | Odp. | |
| 4NT | 5♣/♦/♥/♠ | NOT | 1-4 values |
| X | 0-3 values | ||
| Nast. | 2 worthless values | ||
| Nast.+1 | 2 values + right atu | ||
| Nast.+2 | 2 values + right atu + 1 King | ||
| Nast.+3 | 2 values + right atu + 2 queen | ||