1. Introduction

2. Methodology
2.1. MMT/Megacam data for the 400d WL survey
2.2. Data reduction and calibration
2.3. From images to shape catalogues
2.4. Background Selection
2.5. Shear profile modelling
2.6. Surface mass maps

3. Results for normal clusters
3.1. Cluster detection and lensing morphology
3.2. WL cluster centres
3.3. Shear profiles and NFW modelling
3.4. Mass-Concentration Relations

4. Special Cases
4.1. CL 1701+6414
4.2. CL 1641+4001

5. Verification with independent data
5.1. CFHT Observations
5.2. Comparative shape analysis
5.3. S-statistics from CFHT and MMT
5.4. Photometric redshift results

6. Accuracy of the mass estimates
6.1. Error Analysis
6.2. Redshift Distribution
6.3. Dilution by cluster members
6.4. Uncorrelated Large Scale Structure
6.5. Triaxiality Projection Bias

7. Discussion
7.1. Significance of Cluster Detections
7.2. The Role of Cluster Centres
7.3. Low concentration clusters
7.4. Influence of mass-concentration-relations
7.5. Masking of bright stars
7.6. Further sources of uncertainty

8. Summary and conclusion