obstacles, impediments, roadblocks, barricades, hindrances, bottlenecks, taboos, obstructions, hurdles, glass ceiling, fences, silos, stovepipes, stigmas, checkpoints, constraints, gaps, walls, stereotypes, restraints, challenges, bollards, inequalities, red tape, cordon, logjam, chasms, restrictions, difficulties, iron curtain, disadvantages, limitations, cordon sanitaire, disparities, complexities, fetters, shackles, blockades, monopolies, gates, chainlink fence, structures, inequities, discriminations, firewalls, misunderstandings, stumbling block, burdens, frontiers, hassles, boundaries, palings, preconceptions, paradigms, inhibitions, biases, curbs, pathways, clutter, tariffs, pitfalls, hierarchies, blockages, segregation, constrictions, thresholds, sound barrier, myths, limits, railing, bridge, barbed wire, quotas, drawbridge, hardships, prejudices, signposts, ramps, mechanisms, pressures, problems, ladders, partitions, berm, stanchions, irritants, nexuses, booms, stigmatism, hazards, distortions, prerequisites, scaffolding, windows, illiteracy, straitjacket, divide, strictures, safeguards, gulfs, fragmentation, drawbacks, rigidities, deterrents, diversities, handicaps, vulnerabilities, frictions, issues, prob

common market, ec, eec, eu, europe, european community, european economic community, european union, grade crossing, level crossing