One key element of SIA’s competitive success is that it manages to navigate skillfully between poles that most companies think of as distinct : delivering service excellence in a cost-effective way , at cost levels so low that they are comparable to those of budget airlines. A key challenge of implementing business-level strategies, such as effective differentiation at SIA combined with superior levels of operational efficiency , is the effective alignment of functional strategies such as HR, marketing, or operations with the business level strategy.