| &-Prolog | ⊕ 1990 | ↓ ↑ ⊕ String and List Processing | ⊕ Horn clause | ⊕ Spain | |
| Muse | ⊕ 1990 | ↓ ↑ ⊕ Specialised Languages | ⊕ Horn clause | ⊕ International | Or-Parallel Prolog |
| Prolog-2 | ⊕ 1990 | ↓ ↑ ⊕ String and List Processing | ⊕ Horn clause | ⊕ United Kingdom | |
| Prolog-D-Linda | ⊕ 1990 | ↓ ↑ ⊕ Specialised Languages | ⊕ Horn clause | ⊕ Australia | Linda style Prolog |
| Shared Prolog | ⊕ 1990 | ↓ ↑ ⊕ String and List Processing | ⊕ Horn clause | ⊕ Italy |