Empirical evaluation is a key activity to enable us to reach evidence and learn about the quality of our software artefacts. With aspect-oriented (AO) and related composition techniques, such as model composition techniques, collaboration languages, and feature-oriented programming, fast gaining wide attention in both research and industry environments, there is a pressing need to define proper assessment mechanisms, techniques, and methods to evaluate these new composition techniques. In fact, empirical evaluation is a deep concern to researchers and practitioners in the area of software composition techniques and can be characterized according to two different perspectives: an inter-paradigm perspective, and an intra-paradigm perspective.

In the inter-paradigm perspective, empirical studies along with supporting assessment techniques provide the basic means to improve our understanding of the benefits and drawbacks of composition techniques. According to an intra-paradigm perspective, systematic assessment of composition techniques is imperative through all the software lifecycle phases, from requirements engineering to implementation and maintenance. For example, estimation models and measures of software internal attributes are assessment techniques that can assist software developers, managers, customers, and users to characterize and improve the quality of AO artefacts and products.

As a consequence, assessment is a central issue to enable the effective transfer of new composition techniques to the mainstream of software development and to gain industrial attention for the new techniques. Not surprisingly, empirical evaluation of software composition technologies has been a challenging issue since the rise of the first aspect-oriented programming languages in the past decade. However, there are still a number of complementary questions related to both intra-paradigm and inter-paradigm assessment issues that need to be addressed, such as:

1. What are the proper empirical evaluation approaches to study the effectiveness of AO and related approaches?
2. How to empirically assess the usability and usefulness of AO and related techniques within industrial settings and considering cost bounds?
3. How to support the quality assessment of AO artefacts through the different phases of the software lifecycle?
4. What empirical knowledge to we have about AO and related techniques?
5. Do the existing empirical evaluations already reveal some stable knowledge about AO and related techniques?
6. To what extent aspect-oriented software engineers should rely on existing software metrics and traditional quality indicators?

Topics of Interest. The ESCOT workshop is intended to cover wide range of topics on evaluation of aspect-oriented and related composition techniques, from theoretical foundations to assessment frameworks and empirical studies. We encourage authors to present novel ideas, critiques of existing work, and practical studies and experiments. We also welcome the submission of position papers in all aspects of empirical evaluation of composition techniques, including (but not limited to) the following:

• Lessons learned
• Empirical studies
• Comparative studies between different composition techniques
• Evaluation frameworks
• Software metrics and quality models
• Estimation models
• Validation of assessment methods for software composition techniques
• Assessment methods and tools to different phases of the software lifecycle
• Development of predictive models of defect rates and reliability from real data
• Infrastructure issues, such as measurement theory, experimental design, qualitative modeling and analysis approaches

Workshop Goals. The goals of the ESCOT workshop are the following:

• Share knowledge about existing empirical evaluations of software composition techniques
• Debate the open issues on the evaluation of software composition techniques;
• Bring the attention of the AOSD community to the importance of empirical evaluation
• Foster a collaborative environment for both practitioners and researchers interested in effective evaluation of software composition techniques

Workshop Format and Submissions. The format of the workshop is discussion-oriented that provides in addition to formal presentation also short presentations, followed by discussions, and focused discussion groups. The number of participants is expected to be between 20 and 40. Authors who plan to contribute with a paper are requested to submit a position paper in PDF format to reach the ESCOT co-organizers by January 8 January 20, 2010. Submitted papers can be regular submissions or work in progress (up to 8 pages) as well as position papers (up to 4 pages). Papers will be refereed by at least three reviewers. Moreover, we *especially* encourage authors to present their experience and/or novel ideas on how to evaluate composition techniques. Such papers should offer different or novel perspectives on the workshop topics and they must have a high potential for generating issues that will stimulate the discussions.