This article originally appeared on Forbes.com.

With most buyout deals now shopped by intermediaries and sold through auction, sourcing attractive proprietary deals has become harder than ever. When data research firm Preqin surveyed buyout fund managers in late 2016, 36% of respondents said that it’s more difficult to find attractive investment opportunities compared with a year earlier, and just 2% said it’s easier. Like the latter stages of a gold rush, investors have to get smarter about where and how to dig.

Yet PE firms can improve the odds of sourcing more of the right deals. In its 2016 analysis of 110 private equity firms, Sutton Place Strategies reported that a typical firm will see only 18% of intermediated deals that might be relevant to the firm in its pipeline. Rather than waiting for the offering book to arrive and then reacting at the same time as the rest of the crowd, today’s marketplace requires PE firms to put their best foot forward, actively looking to enhance the quantity and quality of deals entering their funnel.

Based on our experience working with firms on the hunt, it takes a systematic approach consisting of two angles of attack, as explained in Bain & Company’s newly released Global Private Equity Report 2017. Smarter sourcing first hinges on developing a sharp point of view about which types of deals the firm excels in and wants to find, even before any deal becomes a possibility. In concert, firms should expand their network of formal advisers and informal influencers as a way to find targets worth considering.

Clearly articulating the types of businesses that a PE firm wants to buy—the investment sweet spot—provides a roadmap for deal teams. We define the sweet spot as the realm within which a PE firm has sourced and executed its more successful deals. It covers variables such as the private equity firm’s geographic footprint, target ownership, the type of control it seeks to exert and the primary investment thesis. Our analysis has found that deals within a firm’s sweet spot consistently and significantly outperform opportunistic deals that stray from it.

Developing a detailed point of view about which deals to pursue is just half the battle. To uncover more hidden gems, PE firms will have to spend time building out their network. The goal of an expanded network is to gain an edge even before a deal comes to market, by becoming top of mind with intermediaries, building a relationship with the target company’s management team or starting due diligence early.

Two types of networks are worth cultivating: an institutional network of people who are always available when needed, and a temporary network deployed for a specific opportunity or short-term series of deals. Advisers, industry experts, lawyers, bankers, potential partners or targets, potential buyers, intermediaries, ex-CEOs, academics, leaders of trade organizations, and existing or past portfolio management teams all could play a useful role.

Formal advisers, in particular, can address several needs. They improve the quality of deal flow as they filter opportunities, facilitate introductions to management teams or contribute to the underlying analysis of an investment theme. For every 100 potential targets that go into the funnel, we estimate that only 1 or 2 will result in a closed deal. Advisers should help ensure that the top of the funnel is not too wide so that the firm doesn’t waste resources on lower-quality opportunities, or too narrow, which could cause the firm to miss potentially good opportunities. At later stages of the funnel—from which deals go to the investment committee for initial review to final committee decisions to actual bids—advisers help shepherd good deals and kill bad ones.

Some PE firms are deploying their advisers in specific roles. EQT uses experts on call, retaining former senior executives to help pursue assets in industries they know well. Temasek Holdings has taken a slightly different tack, building a network of well-connected executives in Europe and the US—such as PepsiCo CEO Indra Nooyi—who are retained to help with business development.

With proprietary deals so hard to come by, expanding the circle of advisers and influencers, combined with a sharp point of view about what types of deals will make the best fit for a firm, is the best route to opening up new sourcing opportunities.

Hugh MacArthur, Graham Elton, Daniel Haas and Suvir Varma are leaders of Bain & Company’s Private Equity practice.