The Control of Acquired Infections in Health Care is associated with Handwashing. This project aims to validate and adapt the Handwashing Assessement Inventory for Portuguese nurses and it is composed by 3 moments: i) contact with the health institutions of the north and Order of Nurses: presentation of the project and online data collection; ii) data processing and analysis for cross-cultural adaptation and validation; iii) concurrent analysis of the scale by the Attitudes Regardings Guidelines Practices. The choice of this instrument is justified: i) reliability for concurrent analysis for Handwashing Assessement Inventory; ii) identify motivational factors and barriers to compliance with Handwashing procedures. The knowledge of the factors and the results of the application of the scale may be useful in the creation of more assertive strategies to promote adherence to Handwashing. Data processing by SPSS and AMOS; native speaker for translation validation and retroversion.