These activities can provide sexual pleasure to a partner when penetrative intercourse is not possible or desirable for whatever reason.

In Japan, records (including detailed shunga) show that at least some men in relationships with other men did engage in penetrative anal intercourse.

Although this was the ideal, realistically speaking, it is probable that in many such relationships fellatio and penetrative anal intercourse did occur.

Sexually transmitted infections (STIs) can be spread by person-to-person sexual contact, especially penetrative sexual intercourse.

Alternatives to Penetration: Sufferers are often encouraged to explore sexual activity besides penetrative intercourse, which is often a major source of pain.

Further, by removing the adjective widernatürlich ("against nature") they removed the longtime tradition that the law applied only to penetrative intercourse.

Heavy petting covers a broad range of foreplay activities, typically involving some genital stimulation, but not the direct act of penetrative sexual intercourse.