What is secondary (or sympathy) industrial action and is it unlawful? Secondary action (or sympathy strikes as they are sometimes known) would occur if a trade union induces its members to take industrial action against their employer in support of fellow union members -- Published Answers * Will participating in strike action affect my pension? * Action short of strike and deduction from pay * Participation in strikes and the right to take parental leave. * Ending your membership * UCU Fighting Fund 2022