In this kind of design, the introduction of foreign genetic material into the population is allowed, thereby reducing the risk of inbreeding. Performance testing with sister queen groups placed in different testing apiaries is particularly useful for the calculation of breeding values.
More simply, significant differences among families, distributed across different apiaries, reveal a heritable effect of the performance.

An example of an open breeding scheme is the following (from Cornuet and Chevalet, 1987):
First generation: selection based on individual values.
Second generation: colonies ranked according to selection index or breeding value (combination of performance and pedigree data) – the best 10 colonies are used for queen and drone production.
Mating occurs in mating station where selected and unselected drones are present.

Standard methods for rearing and selection of
Apis mellifera queens; IBRA 2013
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