Visual Basic's StrConv function can capitalize the first letter in every word in a string, but it doesn't handle special values like "O'Conner" and "I.B.M" correctly. This program demonstrates StrConv and a custom LwrToUpprCase function.

The LwrToUpprCase function looks through the string seeing which characters are letters and which are not. It capitalizes those that satisfy the rules shown in the comment at the beginning of the function.

' subroutine to normalize 1 piece of data Capitalize
'           Inputs:  char label                            
' 10/29/91
'          Outputs:  Normalized Label
'
' Rules Cap char after [
' ][>][-][.][/][#][0-9][&][Mc][,][(],[\],[|]
'       Cap char after [!][@][$][%][^][*][+][=]["]['(not s)]
'       abbreviations [po][nw][ne][sw][se][ii] are
' capitalized
'       abbreviations [st][th][nd][rd][c/o]    are not
' capitalized
'               words [of][and]                are not
' capitalized
Public Function LwrToUpprCase(ByVal edit$) As String
    Dim A$, b$, c$, I%
    On Error Resume Next

    If Len(Trim(edit$)) = 0 Then
        LwrToUpprCase = edit$
        Exit Function
    End If

    edit$ = edit$ + Space$(3)       'end of word match ???
    Mid$(edit$, 1, 1) = UCase$(Mid$(edit$, 1, 1)) 'cap
        ' first char
    If Mid$(edit$, 1, 3) = "Po " Then
        Mid$(edit$, 1, 3) = "PO " 'PO Box cap
    End If
    b$ = "NwNeSwSeIi"       'NW NE SW SE II
    If Mid$(edit$, 1, 2) = "Mc" Then
        Mid$(edit$, 3, 1) = UCase$(Mid$(edit$, 3, 1))
    End If
    If Mid$(edit$, 1, 1) > Chr$(47) And Mid$(edit$, 1, 1) < _
        Chr$(58) Then
        Mid$(edit$, 2, 1) = UCase$(Mid$(edit$, 2, 1)) 'nos
            ' 0 - 9
    End If
    c$ = " >-./#&,(!@$%^*+=\|" & Chr(34)
    If InStr(c$, Mid$(edit$, 1, 1)) > 0 Then
        Mid$(edit$, 2, 1) = UCase$(Mid$(edit$, 2, 1))
    End If
    For I% = 2 To Len(edit$)
        If InStr(b$, Mid$(edit$, I%, 2)) > 0 Then
            If Mid$(edit$, I% - 1, 1) = " " And Mid$(edit$, _
                I% + 2, 1) = " " Then
                Mid$(edit$, I%, 2) = UCase$(Mid$(edit$, I%, _
                    2))
            End If
            I% = I% + 2
        End If
        If Mid$(edit$, I%, 4) = " of " Then 'dont cap word
            ' "of"
            I% = I% + 2
            GoTo skipcapchar
        ElseIf Mid$(edit$, I%, 5) = " and " Then 'dont cap
            ' word "and"
            I% = I% + 3
            GoTo skipcapchar
        
        ElseIf Mid$(edit$, I%, 5) = " c/o " Then 'dont cap
            ' abbrev c/o
            I% = I% + 3
            GoTo skipcapchar
        End If
        If InStr(c$, Mid$(edit$, I%, 1)) > 0 And I% < _
            Len(edit$) Then
            Mid$(edit$, I% + 1, 1) = UCase(Mid$(edit$, I% + _
                1, 1))
        End If
        If Mid$(edit$, I%, 1) = Chr$(39) And Mid$(edit$, I% _
            + 1, 1) <> "s" Then
            Mid$(edit$, I% + 1, 1) = UCase$(Mid$(edit$, I% _
                + 1, 1)) 'O'Malley's
        End If
        If Mid$(edit$, I%, 2) = "Mc" Then
            Mid$(edit$, I% + 2, 1) = UCase$(Mid$(edit$, I% _
                + 2, 1))
        End If
        If InStr("0123456789", Mid$(edit$, I%, 1)) > 0 Then _
            'nos 0-9
            A$ = Mid$(edit$, I% + 1, 2)
            If A$ <> "st" And A$ <> "th" And A$ <> "nd" And _
                A$ <> "rd" Then
                Mid$(edit$, I% + 1, 1) = UCase$(Mid$(edit$, _
                    I% + 1, 1)) 'no's 0-9
            End If
        End If
skipcapchar:
    Next I%
    edit$ = RTrim$(edit$) 'trim space added earlier

    LwrToUpprCase = edit$
End Function