The problem of verification of international treaties or agreements is one of obtaining reliable, continuous and highly accurate evidence that treaties are being honoured by their signatories, without infringing upon such principles of international law as sovereignty, territorial integrity and non-interference in domestic affairs. While the verification problem arises in part from the degree of effectiveness of the national technical means available for monitoring purposes, it actually stems more from the cold-war legacy of mistrust and suspicion in relations between countries with different social systems, and by the constant fuelling of this mistrust and suspicion by the opponents of international disarmament.