This chapter (Based on: Levin MS (2012) Composition of modular telemetry system with interval multiset estimates. Electronic preprint, p 9, July 25, 2012. http://arxiv.org/abs/1207.6051 [cs.SY]) addresses describes combinatorial synthesis of a modular telemetry system. Hierarchical morphological design with interval multiset estimates is used. The following system design problems are examined: hierarchical modeling, modular design, analysis and improvement of solutions, aggregation of structured solutions. Real-world numerical examples illustrate the above-mentioned design problems.