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    <p>You are missing the <code>virtual</code> keyword. In C++ methods are not virtual by default like they are in some other programming languages (e.g., Java). Try the following instead:</p> <pre><code>#include &lt;iostream&gt; class User { static const int min_pass_len = 10; public: virtual ~User() {} virtual int getPasswordLength() const { return min_pass_len; } }; class AdminUser: public User { static const int min_pass_len = 42; public: virtual ~AdminUser() {} virtual int getPasswordLength() const { return min_pass_len; } }; int main() { AdminUser a; User u, *p = &amp;a; std::cout &lt;&lt; u.getPasswordLength() &lt;&lt; "\n" &lt;&lt; a.getPasswordLength() &lt;&lt; "\n" &lt;&lt; p-&gt;getPasswordLength() &lt;&lt; "\n" &lt;&lt; std::endl; return 0; } </code></pre> <p>If you want to get rid of the method altogether, then either use the example of the <a href="https://stackoverflow.com/questions/4481285/how-to-store-a-magic-number-for-each-derived-class-that-is-then-accessible-from-t/4481363#4481363"><em>"curiously reoccuring template pattern"</em> mentioned by Sanjit</a> or externalize the constant instead embedding it within the class. I was thinking of something similar to how <code>std::numeric_limits</code> is implemented:</p> <pre><code>template &lt;typename T&gt; struct UserTraits { static const int minimum_password_length = 0; }; template&lt;&gt; struct UserTraits&lt;User&gt; { static const int minimum_password_length = 10; }; template&lt;&gt; struct UserTraits&lt;AdminUser&gt; { static const int minimum_password_length = 10; }; int main() { std::cout &lt;&lt; UserTraits&lt;User&gt;::minimum_password_length &lt;&lt; "\n" &lt;&lt; UserTraits&lt;AdminUser&gt;::minimum_password_length &lt;&lt; "\n" &lt;&lt; std::endl; return 0; } </code></pre> <p>I usually prefer the first approach since it works when you have a pointer to an instance. The latter method isn't nearly as useful since you cannot use it to extract the constant from an instance without resorting to writing a free function and even then you loose the dynamic typed aspect.</p> <pre><code>template &lt;typename T&gt; int getPasswordLength(T*) { return UserTraits&lt;T&gt;::minimum_password_length; } template &lt;typename T&gt; int getPasswordLength(T&amp;) { return UserTraits&lt;T&gt;::minimum_password_length; } </code></pre> <p>The problem with this approach is that you would get the wrong result if you called <code>getPasswordLength(p)</code> using <code>p</code> in the first snippet.</p>
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