Zero-based Budgeting Ensures Responsible Oversight (ZERO) Act of 2017 This bill requires the President to submit annual department and agency budgets that include: a description of each activity for which funds were appropriated during the current year or are requested for the budget year; the legal basis for each activity; three alternative funding levels and the priorities that could be accomplished with each, including at least two levels that are below the current funding level; and measures of cost efficiency and effectiveness for each activity. The Office of Management and Budget must publish guidelines to carry out this bill by assuming the baseline budget of each department or agency to be zero and requiring each proposed expenditure to be justified as if it were new.