'Adherency' is a form of membership of The Salvation Army which varies from country to country. It never requires the full acceptance of Salvation Army regulations that 'soldiership' (full membership) requires, but in many countries the adherent signs a Certificate of Recognition.
One widely used certificate declares: 'This certificate confirms that ____ is an Adherent Member of The Salvation Army. An adherent member of The Salvation Army is a person who believes in the Lord Jesus Christ and seeks to follow and be like him; participates in the worship, fellowship, service and support of a local Salvation Army congregation; and identifies with the Army's Mission Statement.
An adherent member is a person 14 years of age or over, who meets the definition of adherency given above, and who is not an active member of any other religious body. The Salvation Army affirms all who sign the certificate, recognizes this as a positive step in a personal journey and pledges ongoing encouragement and pastoral guidance as this journey of faith unfolds.