Roughly the size of a soda can, sitting on a bookshelf, a relatively harmless device may be turning friends away from your home. The elephant in your living room is your Internet-connected camera, a device people are increasingly using for peace of mind in their homes. But few stop to think about the effect these devices may have on house guests. Should you tell your friends, for instance, that they’re being recorded while you all watch the big game together?

“It’s certainly new territory (领地), especially as home security cameras become easier to fix,” says Lizzie Post, president of the Emily Post Institute, America’s distinguished manners advisors. “I think it will be very interesting to see what manners appear in terms of whether you tell people you have a camera or not, and whether guests have a right to ask that it be turned off, if it’s not a security issue.” Post wants to make clear that she’s not talking about legal rights, but rather personal preference.

When it comes to security cameras, Post says it’s a host’s responsibility to make sure guests feel comfortable within their home. If the host casually acknowledges that there is a camera in the room by telling a story about, it that may be enough to provide an opening for a guest to say if they are uncomfortable.

However, if a contractor (合约工) is working in your home, you don’t need to tell them that there are cameras watching. Then again, the camera can also work in contractors’ favor. “If anything does go wrong while they’re in the house, they don’t want to be blamed for it,” she says. “In fact, the camera could be the thing that proves that they didn’t steal the $20, or knock the vase off the table.”

Migration (迁移) has become a flashpoint for debate in many countries. But research from the McKinsey Global Institute(MGI) finds that it generates significant economic benefits-and more effective integration of immigrants (移民) could increase those benefits.

Moving more labor to higher-productivity settings boosts global GDP. Migrants of all skill levels contribute to this effect, whether through entrepreneurship (创业) or through freeing up natives for higher-value work. In fact, migrants make up just 3. 4 percent of the world’s population, bur MGI’ research finds that they contribute nearly 10 percent of global GDP. They contributed roughly $6. 7 trillion to global GDP in 2015-some $3 trillion more than they would have produced in their origin countries. Developed nations realize more than 90 percent of this effect.

Employment rates are slightly lower for immigrants than for native workers in top destinations, but this varies by skill level and by region of origin. Wide-ranging academic evidence shows that immigration does not harm native employment or wages, although there can be short-term negative effects if there is a large inflow of migrants to a small region, if migrants are close substitutes for native workers, or if the destination economy is experiencing a downturn.

Realizing the benefits of immigration depends on how well new arrivals are integrated (融合) into their destination country’s labor market and into society. Today immigrants tend to earn 20 to 30 percent less than native-born workers. But if countries narrow that wage gap to just 5 to 10 percent by integrating immigrants more effectively across various aspects of education, housing, health, and community engagement, they could generate an additional boost of $800 billion to $1 trillion to worldwide economic output annually. This is a relatively conservative goal, but it can produce broader positive effects, including lower poverty rates and higher overall productivity in destination economies.

The stakes are high. The success or failure of integration can reverberate (回荡) for many years, influencing whether second-generation immigrants become fully participating citizens who reach their full productive potential or remain in a poverty trap.