 In 1863 Tallack became secretary to the Society for the Abolition of Capital Punishment, exchanging this in 1866 for the same post in the Howard Association, which he held till 31 December 1901.As an activist for penal reform, he visited not only the continent of Europe, but Egypt, Australia, Tasmania, Canada, and the United States.He advocated in particular for more prison visitors, and lecturers.