This document presents a new interactive image segmentation method called Advanced Maximal Similarity Based Region Merging (MSRM) using user interactions. The method first segments the image using multi-level thresholding. The user then marks regions of the desired object with markers. Regions are represented by color histograms and similarity is measured using Euclidean distance of mean color values. Regions are merged based on similarity, first merging marked and unmarked object regions, then merging remaining unmarked regions. Results show the proposed MSRM method achieves higher true positive rates and lower false positive rates than other interactive segmentation methods.