The aim of the work: is to assess the response of LABC to neo-adjuvant chemotherapy by Tc-99m MIBI & Tc-99m (V)DMSA scintimammography in relation to histopathological evaluation. Materials & Method: 24 patients with locally advanced breast carcinoma, were included. Pre-neo adjuvant chemotherapy scintimammography using Tc-99m MIBI& Tc-99m (V) DMSA was done. After 3-4 courses of neo-adjuvant chemotherapy, scintimammography was repeated. The degree of change in MIBI & (V)DMSA uptake from pre-therapy scan to post-therapy scan was calculated. Correlation between the degree of change of MIBI & (V)DMSA and histopathological percentage of necrosis was done.Results: Good response was evident in 9 patients, 88.8% of them showed significant degree of change in Tc-99mMIBI uptake ratio while only 33.4% showed partial degree of change in (V)DMSA uptake ratio. The mean percentage of change in MIBI uptake in this group was 51.6%, while that of (V)DMSA was -6.6%. Partial response was evident in 5 patients. All of them (100%) showed partial degree of change in MIBI uptake while (V)DMSA uptake showed no change in all the five patients. The mean value of change of MIBI was 19.6%, while that of (V)DMSA was-20.8%. Bad response: 10 patients showed bad response. All the ten patients (100%) showed no change in MIBI uptake ratio, while 50% showed no changed in (V)DMSA uptake ratio. The mean percentage of change in MIBI was 2.59 while that of (V)DMSA was -12.4 There was highly statistically significant correlation between degree of change of Tc-99m MIBI & percentage of histopathologic necrosis (P < 0.01), whereas no significant correlation was found between degree of change of (V)DMSA & percentage of necrosis (P > 0.05).Conclusion: Tc-99m MIBI scintimammography is valuable in assessment of response of LABC to neo-adjuvant chemotherapy, while Tc-99m (V) DMSA plays no role in assessment of response to neo adjuvant chemotherapy.