Relationship of international law and municipal law — Treaties — EC Treaty, 1957 — Supremacy of EC law over conflicting provisions of national law — Whether EC law taking precedence even over national constitutional provisions

Treaties — Successive treaty obligations — Existing treaty obligations — EC Treaty, Article 234 — Whether authorizing Member States to exercise rights in intra-Community relations under treaties concluded prior to the EC Treaty which conflict with Community obligations — European Convention on Establishment, 1955, Article 13 — Whether capable of constituting derogation from Article 48(4) of EC Treaty

Treaties — Derogations — Existing treaty obligations — EC Treaty, Article 233 — Scope of derogation permitted to members of Benelux Union from EC treaty rules — Benelux Treaty, 1958, Article 61 — Whether limiting scope of application of Article 48 of EC Treaty — Protocol to EC Treaty on Grand Duchy of Luxembourg, Article 2 — Scope of right of Grand Duchy to have its special demographic situation taken into account

Aliens — Freedom of movement of workers — EC rules — Scope of derogations — Employment in public service — Nationality requirement — Permissibility — EC Treaty, Article 48(4) — Scope of exception

International tribunals — Court of Justice of the European Communities — Jurisdiction — Actions against Member States for failure to fulfil treaty obligations — EC Treaty, 1957, Articles 169–71 — Finding of breach by Court of Justice of the European Communities — Whether Court empowered to grant period of grace for compliance with its judgments — The law of the European Community