This chapter provides an introduction and overview of how to plan and undertake the collection of plant genetic samples in the field, and once collected how the samples should be processed, stored and made available for utilization. As such it includes a practical overview of expedition planning and of how to collect germplasm, voucher specimen and passport data. Germplasm collection involves the sampling and ex situ conservation of seed, tubers, cuttings, corms and vegetative plants away from the site where the material was originally located. The types of collection sites, and how each may be sampled are reviewed. The special cases of collecting fruit or other trees, forages, wild species, vegetative material and indigenous knowledge are discussed. A model for a generalized germplasm collection form and a collection report structure is presented, and the processing and final deposition of the conserved germplasm is summarized.