Int. J. Procurement Management, Vol. 10, No. 4, 2017 461 Copyright © 2017 Inderscience Enterprises Ltd. Retailer’s ordering policy for deteriorating imperfect quality items when demand and price are time-dependent under inflationary conditions and permissible delay in payments Mandeep Mittal Amity School of Engineering and Technology, 580-Delhi Palam Vihar Road, Bijwasan, New Delhi-110061, India Email: mittal_mandeep@yahoo.com Aditi Khanna and Chandra K. Jaggi* Department of Operational Research, Faculty of Mathematical Sciences, New Academic Block, University of Delhi, Delhi-110007, India Fax: 91-11-27666672 Email: dr.aditikhanna.or@gmail.com Email: ckjaggi@yahoo.com Email: ckjaggi@or.du.ac.in *Corresponding author Abstract: The present paper investigates an inventory model with unreliable supply, where each received lot may have a random fraction of defective items with known distribution. Thus, the inspection of lot becomes essential in almost all the situations, especially when the items are of deteriorating in nature. Moreover, in today’s competition inherited business world, organisations use many promotional tools in order to increase their sales. One such tool is a permissible delay in payments, i.e., the buyer does not have to pay for the goods purchased immediately rather can defer the payment for a prescribed period given by the supplier. Further, in today’s wobbling economy, especially for long-term investment, the effects of inflation cannot be disregarded as uncertainty about future inflation may influence the ordering policy. Being motivated by these aspects, the present paper investigates the impact of inspection on retailer’s ordering policy for deteriorating items under permissible delay in payments when demand and price both varies with the passage of time. Finally, the model has been analysed and validated with the help of numerical examples. A comprehensive sensitivity analysis is also presented which provides important managerial implications. Keywords: inventory; deterioration; inspection; time-dependent demand; permissible delay in payments; inflation. Reference to this paper should be made as follows: Mittal, M., Khanna, A. and Jaggi, C.K. (2017) ‘Retailer’s ordering policy for deteriorating imperfect quality items when demand and price are time-dependent under inflationary conditions and permissible delay in payments’, Int. J. Procurement Management, Vol. 10, No. 4, pp.461–494.