142 CASE 7 Estimating a User-Centered Design Effort schedules she had created. Comparing the differences and reviewing e-mails, she identified many guidelines for realistic estimating and scheduling of UCD projects, described in the Summary below. Summary "The difficult we do immediately. The impossible takes a little longer" (slogan of the U.S. Army Air Forces, after a quotation by Charles Alexandre de Calonne, 1734­1802). Defining a UCD effort is challenging when budget and calendar time are limited. Accurate estimating builds trust and promotes a spirit of creative compromise. Shea Rose's experience at Apollo Appraisal Systems is typical of many situations in the UCD profession: · UCD professionals often move during their career growth from a setting where they're part of a supportive group to an organization where they are the primary UCD practitioner. UCD professionals usually work in organizations that have a large highly structured engineering group. UCD activities must coordinate with engineering activities and their schedules. UCD professionals are strongly motivated to perform high-quality research and design that meet users' needs and goals. Therefore UCD professionals must estimate and define UCD activities that satisfy both their own professional goals and the goals--and constraints--of their coworkers and their organization. · · · Shea's work on the second enhancement to XperComp went much more smoothly because she followed these guidelines: · · · · · · Estimate in working hours, not just weeks. Use ranges for hours if you are unsure. Allow time for project management. Allow time for other responsibilities that are not related to this project. Consider the schedules of other contributors to the overall project. Allow time for other team members' contribution to the research (reviews, design meetings). Be realistic in how much calendar time it will take to recruit participants.