The performance-based analysis for the low-storey building type structures are generally carried out, as those buildings were isolated single standing buildings with no interaction with adjacent buildings. Incorporating the interaction of the adjacent buildings in seismic performance and risk (retrofitting) analysis by using proper modelling techniques seems important by means of obtaining the deviation of the results from the conventional analysis results of isolated single modelled structures. Literature review has been carried out for the following topics; adjacent building models, push-over analysis, earthquake acceleration, time series database analysis and scaled records, time history analysis of equation of motion with Newmark-beta method and fragility curves for building performance levels. The aim of this study is the evaluation of vulnerability risk via fragility curves for seismic performance of adjacent buildings as interacting structures. Results show that interacted and isolated analysis types yields different seismic performance levels.