European sexually transmitted infections (STIs) diagnostic and therapeutic guideline were firstly published in 2001. They are updated on regular bases in line with the progress of scientific medical knowledge and changes in the epidemiological situation. The evolution of antimicrobial resistance in bacterial microorganisms is also of major concern. We present the latest, since 2020, Guideline regarding diagnostics, treatment, principles of after-treatment follow-up and partners’ management in four bacterial STIs, namely: syphilis, gonorrhoea, infections with Mycoplasma genitalium and, published in 2025, Chlamydia trachomatis. In addition, the statement of International Union against Sexually Transmitted Infections-Europe on prophylactic doxycycline use in bacterial STIs is briefly discussed.