Copy all files from directory to another with Grunt.js copy

The flatten: true option as in this answer might work for some cases, but it seems to me that the more common requirement (as in my case) is to copy a folder and its sub-folder structure, as-is, to dest. It seems that in most cases if you have sub-folders, they are probably being referenced that way in code. The key to doing this is the cwd option, which will preserve folder structure relative to the specified working directory:

copy: {
  files: {
    cwd: 'path/to/files',  // set working folder / root to copy
    src: '**/*',           // copy all files and subfolders
    dest: 'dist/files',    // destination folder
    expand: true           // required when using cwd
  }
}

This task will maintain folder structure if you specify a file glob. What you want is the flatten option which will remove the structure.

{
    expand: true,
    flatten: true,
    src: ['src/html/css/fonts/**'],
    dest: 'dist/myvoice/css/fonts/',
    filter: 'isFile'
}

Find the rest of the available options in the Github repo. Hope this helps.