| ↔ Order by name | ↔ Order by year | ↔ Order by year reverse | ↔ Order by Type | ↔ Order by Sammet category |
| &ACE | ⊕ 1995 | Spain | |||
| &-Prolog | ⊕ 1990 | ↓ ↑ ⊕ String and List Processing | ⊕ Horn clause | Spain | |
| ACE | ⊕ 1994 | ↓ ↑ ⊕ Experimental and other | Spain | Parallel logic language | |
| CIAO | ⊕ 1994 | ↓ ↑ ⊕ Experimental and other | ⊕ Horn clause | Spain | Distributed And/Or parallel prolog |
| Excalibur | ⊕ 1988 | Spain | |||
| O'Ciao | ⊕ 2002 | Spain | |||
| PROLIX | ⊕ 2000 | Spain |