In Guatemala the Environmental Regulation on Assessment, Control and Monitoring (Governmental Agreement No. 137-2016) regulates the EIA system.  It contemplates the procedures to be followed in the processes of evaluation, control and environmental monitoring, which are mandatory for activities mentioned in the so-called lista taxativa (screening list). This list is an annex to the Regulation 137-2016 and is currently being updated (expected date of publication 26 Sept. 2019).
This regulation has an emphasis on EIA, but SEA appears as one of the instruments (art. 13). However, the SEA procedure and approach is not further operationalised.  

The Ministry of Environment and Natural Resources (MARN) is the responsible authority.