A family can have a good investment advisor, a good accountant and a good attorney and still have a problem. Each advisor sees a different part of the family’s financial life.

The investment advisor sees the portfolio. The accountant sees the tax position. The attorney sees the legal structure. Another professional may handle retirement accounts or assets in a different country.

The family does not live according to those professional boundaries. A decision about company shares can affect taxes, liquidity and concentration at the same time. Moving to another country can change the relevance of retirement accounts, insurance and investment structures that were created years earlier. Selling a business can create liquidity while also changing the family’s tax position, investment needs and estate planning.

This is particularly relevant for families whose members, assets and financial arrangements span several countries. Retirement accounts may remain in a country where the family no longer lives. Employer equity may have been earned across several jurisdictions. Property, brokerage accounts and private investments may be held in different places and currencies.

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Adding specialists is often necessary. It does not solve the coordination problem by itself.

An investment advisor may build a diversified portfolio without knowing that the family holds a large employer-equity position elsewhere. A tax advisor may recommend a transaction without seeing how it affects the liquidity needed for another family goal. An attorney may structure assets without knowing that a family member plans to move to another country.

Each recommendation can make sense on its own and still create a problem when combined with the others.

Liquidity is a good example. A family may have substantial net worth but relatively little capital available for the next five years. Some wealth may sit in retirement accounts. Some may be concentrated in employer shares. Property may represent a large part of net worth. Private investments may require additional capital before returning any.

Looking only at the liquid portfolio can therefore give the wrong answer to a basic question: how much financial flexibility does the family actually have?

The same applies to investment risk. A portfolio can be diversified while the family is highly concentrated. A senior executive may hold employer shares outside the managed portfolio and continue to receive salary, bonus and future equity from the same company. A business owner may have most of the family’s wealth tied to the same industry in which the investment portfolio also has exposure.

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The portfolio is only part of the balance sheet. For international families, currencies create another connection between decisions. The currency in which assets are held may be different from the currency in which the family expects to spend. Children may study in one country while the parents plan to retire in another. Property, pensions and investments may each create different currency exposures.

None of this means that one professional should try to replace all the others. Cross-border families often need specialist tax, legal and investment expertise in more than one jurisdiction. But someone needs to know how the pieces fit together.

That starts with the family’s goals. Where does the family expect to live? When might work become optional? What capital will be needed over the next five or ten years? What does the family want to provide for children or grandchildren? Which risks are deliberate and which simply accumulated through years of career and investment decisions?

An investment decision can then be considered alongside assets held elsewhere. A tax decision can be evaluated together with its effect on liquidity. Estate planning can reflect where family members live and where assets are held. Employer equity can be viewed as part of the family balance sheet rather than simply as compensation.

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One change in the family’s plans can affect several advisors at once. If the family plans to move, the tax and legal implications may affect investment decisions before the move takes place. If an executive wants to stop working earlier, liquidity requirements change. If a concentrated position is reduced, the investment portfolio may need to be reconsidered. If a large private investment is made, the amount of risk the family can take elsewhere may change.

The advisors do not need to do one another’s jobs. They need to be working from the same picture. A family may need several advisors. It still has one balance sheet and one set of goals. Someone needs to own the whole picture.