Abstract: Checking Proofs in the Metamathematics of First Order Logic (M. Aiello, R. Weyhrauch). Foundations. Issues in Computational Reflection (P. Maes). Meta in Logic (D. Perlis). Meaning in Knowledge Representation (L. Steels). Reasoning by Introspection (K. Konolige). Introspective Fidelity (M. Genesereth). Commonsense Set Theory (D. Perlis). Implementations. Control-Related Meta-Level Facilities in LISP (J. des Rivieres). The Mystery of the Tower Revealed: A Non-Reflective Description of the Reflective Tower (M. Wand, D. Friedman). Communication between LISP and Horn Clauses by Mutual Reflection (R. Ghislanzoni, L. Spampinato, G. Tornielli). The ObjVlisp Kernel: A Reflective Lisp Architecture to Define a Uniform Object-Oriented System (P. Cointe). Conceptual Reflection and Actor Languages (J. Ferber). Evaluation and Reflection in FOL (D. Nardi). OMEGA: An Integrated Reflective Framework (M. Simi, E. Motta). Meta-Levels in SOAR (P. Rosenbloom, J. Laird, A. Newell). Applications. The Uses of Metaknowledge in AI Systems (L. Aiello, G. Levi). Reasoning about Self-Control (J. Batali). A Multi-Context Monotonic Axiomatization of Inessential Non-Monotonicity (F. Giunchiglia, R. Weyhrauch). Declaratively Programmable Interpreters and Meta-Level Inference (B. Welham). A Meta-Level Architecture for Expert Systems (L. Sterling). Object Level Reflection of Inference Rules by Partial Evaluation (P. Coscia et al.). Functional Meta-Level for Logic Programming (P. Mancarella, D. Pedreschi, F. Turini). Meta-Level Extensions of Logic and Machine Learning (P. Brazdil).