A well-known dilemma in strategic marketing is whether a firm can be simultaneously both efficient in its existing business and innovative in creating new business (Atuahene-Gima 2005; Christensen 1997). Beleaguered companies such as AOL, Kmart, Motorola, Nokia, Polaroid, and Sears are examples that were once highly efficient in serving customers, but partly due to that efficiency in their existing business, paradoxically failed to introduce innovations. The potential tension “between innovation and efficiency—is one that’s bedeviling CEOs everywhere” (Hindo 2007). Two questions regarding the efficiency–innovation tradeoffs are especially intriguing to researchers and managers alike. First, to what extent are such tradeoffs driven by efficient firms’ lack of eagerness or willingness to innovate in the first place, or lack of ability to innovate and promote innovations? Second, can certain strategic marketing factors mitigate the tension of such tradeoffs? Indeed, anecdotal evidence indicates that not all firms that are efficient in their current business (e.g., Charles Schwab, Capital One) lack innovative thrust. In fact, efficient firms may actually be eager to innovate: Nokia, for instance, originally innovated an online “app store” service as well as touchscreen smartphones and Internet tablets in the 1990s and 2000s, much earlier than Apple (Ben-Aaron 2009; MobileGazzette 2008). Similarly, Polaroid was originally a pioneer in developing digital cameras and imaging services in the 1980s (Tripsas and Gavetti 2000). The eventual failures of Nokia’s and Polaroid’s innovation efforts, thus, do not seem to be due to their lack of eagerness to innovate, but perhaps the inability to manage the efficiency–innovation tension. In contrast, other companies seem to be able to manage this tension. For instance, in financial services, Charles Schwab is often commended both for its efficiency and its innovativeness, and the firm itself feels the “need to invest in innovation to maintain a competitive edge” (Gilson 2012). Against this backdrop, we focus on two questions: (1) What exactly are the tradeoffs and tensions between a firm’s existing efficiency, innovativeness in its new offerings, and new offering performance? And (2) how can strategic marketing assets such as customer base and advertising intensity mitigate the tradeoffs? Should such assets help to alleviate the inherent tension, they would give executives tools to pursue both efficiency and innovation at the same time and succeed with their new innovative offerings. Empirically, we focus on the service sector, whereby the actual technical development of innovations is not very costly in tangible financial terms (Crawford and di Benedetto 2008; Droege et al. 2009; Thomke 2003)―making the intangible firm capabilities most likely determinants of (innovation) performance rather than tangible resources (cf. Vorhies, Morgan, and Autry 2009). Therewith, we examine our research questions with a comprehensive census dataset of all new service introductions (n≈500) in one national market: The Finnish mutual funds industry (1997–2010). The sector of financial services is especially relevant for the efficiency–innovation tradeoffs because in this sector, many firms are compelled to engage in both efficient operations and effective (financial) innovations. Our empirical focus on all firms in one market precisely identifies and measures the efficiency levels of all competing firms, relative to the best-performing competitors, as well as innovativeness (earliness) in introducing new services compared to all rivals. For a marketing perspective, we focus on firms’ existing customer-perceived service efficiency (over the entire portfolio of existing services, i.e., funds)—defined through the ratio of output value that customers obtain from the firms’ current services to the (customer) cost inputs. We also carefully delineate between (a) innovativeness of a new service introduction and (b) its performance. Doing so can reveal the potentially contradictory effects of existing efficiency on new service innovativeness (willingness to innovate) vis-à-vis new service performance (ability to make innovations succeed). As our key results, we firstly identify and explicate the baseline efficiency–innovation tradeoffs. Specifically, our results suggest that while existing service efficiency increases the innovativeness of new services introduced by the firm, it simultaneously (1) leads to decreased business performance for the new services introduced and (2) diminishes the positive influence of innovativeness on performance. In sum, these findings imply that on the baseline, highly efficient service firms may be too eager to innovate, considering the sub-par performance they are likely to receive for those innovations. Secondly, our results reveal two strategic marketing factors, which have the potential to mitigate the tradeoffs. We find that the firm’s (a) focused customer base and (b) high advertising intensity can nullify the negative effect of existing service efficiency on innovativeness and the negative moderating effect of efficiency on the innovativeness–performance link.