Sometimes species will be introduced intentionally, however this is rare.
China has had a long history of intentionally introducing species considered beneficial.
As in the case of kudzu, people may intentionally introduce a plant for a specific purpose.
Impurities are generally avoided, but can be introduced intentionally as a way to control certain properties of the diamond.
Other locations in California have been used as refuges for this pure variety by intentionally introducing the fish into the location.
Platydemus manokwari has also sometimes been introduced intentionally, as a biological control agent.
It has been intentionally introduced to other parts of the world as a pet and as pest control, with mixed results.
A pseudobezoar is an indigestible object introduced intentionally into the digestive system.
When Fleming pointed out that because the problems in the data improved the experimental results, it seemed that they were introduced intentionally.
Sometimes human populations intentionally introduce species into new landscapes to serve various purposes, ranging from decoration to erosion control.