The other solutions I've seen here so far are based on some system definitions, but it's in fact possible to have sudo use the current PATH (with the env command) and/or the rest of the environment (with the -E option) just by invoking it right:

```
sudo -E env "PATH=$PATH" <command> [arguments]
```

In fact, one can make an alias out of it:

```
alias mysudo='sudo -E env "PATH=$PATH"'
```

(It's also possible to name the alias itself sudo, replacing the original sudo.)