For general questions probing for motivations and alternatives, qualitative techniques such as customer interviews, focus groups, and general surveys are effective.
For testing alternatives, tracking trends, or estimating measurable criteria, quantitative techniques are useful; often professional services are employed to design and implement statistically valid models and controlled experiment surveys. You can also use ergonomic testing and prototypes to assess acceptance of new ideas.
Select techniques that will yield the information you require, and develop a plan for the research. Determine who will lead the research effort, and identify the skills and staffing that will be required.
Develop a proposal for the research, ...