In 2003, a national multi-sectorialHandwashing Initiative (HWI) was created in Peru to increasehandwashing with soap among mothers and children. The earlyyears of the HWI focused on laying groundwork, including aformative research study in 2004; the creation of aconsultative committee by the Ministry of Health (MoH); anda national decree formalizing the HWI. The Water andSanitation program (WSP) has coordinated the HWI since itsinception. This learning note profiles the behavior changecomponent of the second phase with a focus on how it wasdesigned, implemented, and monitored. Challenges and lessonslearned are included to assist program managers as they makedecisions to develop and manage a handwashing promotioninitiative. Peru provides an interesting case study becausethe intervention itself is interwoven with efforts tostrengthen capacity, policies, partnerships, and otheraspects of the enabling environment required to sustainhandwashing with soap programs. Though detangling thesevarious program components is a challenge, this note on thebehavior change journey attempts to do so.