Effective communication and life-long learning skills have been identified as critical competencies for the engineering workplace in ABET's accreditation guidelines, in NAE's vision for the engineer of 2020, and by professionals working in the field. Engineering educators have responded with increased attention to communication instruction and the development of life-long learning skills; however, more work remains to be done to prepare students to communicate in today's increasingly complex engineering workplace. Research has shown that developing communication skills - particularly writing - involves sustained, and often solitary, intellectual effort that requires motivation. The work reported here explores motivation for professional communication, through the application of the pedagogical intervention, Preparedness Portfolios and Portfolio Studios (PPPS). The findings from this multiple-case study of ten engineering undergraduate students creating preparedness e-portfolios strongly suggest that the PPPS pedagogy provides a fruitful environment for revealing, and enhancing, students' motivation for developing professional communication skills for the engineering workplace. The findings align with various components of existing motivational frameworks.