Lanham Act, a popular name for the Federal Trademark Act of 1946 is the Act which deals with the federal statutes of trademark law in the United States. The Act inter alia precludes various sphere of action in the area of trademark usage like trademark infringement, trademark dilution etc. Among these comes another concept called "trademark dress." This is a concept which originated from the way a product is packed or a product's total image or appearance. It is distinctive, non-functional, and distinguishes a trader's or manufacturer's products or services from those of others.
Typically, trademark consists of only a set of words or a logo. On the other hand, Trade Dress includes appearances like size, color or combinations of color, shape, a product's packaging or atmosphere inside a store, restaurant etc. Moreover, trade dress encompasses both packaging and design of products.
The Act which was enacted in 1946 precluded a product's “false description or representation” by a “person who shall with knowledge of the falsity” put the product on trade. This Act did not refer to trade dress protection as such. Later on the courts extended protection granted under Section 43(a) of the Lanham Act to trade dress also basically creating a federal law to enhance fair trade practices.
Two Pesos, Inc. v. Taco Cabana, Inc., 505 U.S. 763 (1992) is a landmark case in the history of trademark dressing in US. In 1987, Taco Cabana sued Two Pesos in the United States District Court of the Southern District of Texas for trade dress infringement under § 43(a) of the Lanham Act, 15 U.S.C. § 1125(a) (1982 ed.) and for theft of trade secrets under Texas common law. The case was then put forward to a jury. The jury was asked to put forth its verdict by answering five questions promulgated by the trial judge. The answers to these questions were as follows:
1) Taco Cabana has a trade dress;
2) Taken as a whole, the trade dress is nonfunctional;
3) The trade dress is inherently distinctive;
4) The trade dress has not acquired a secondary meaning in the Texas market; and
5) The alleged infringement creates a likelihood of confusion on the part of ordinary customers as to the source or association of the restaurant's goods or services. 
In view of this verdict Taco Cabana's trade dress was safeguarded as it either was naturally unique or had derived a meaning which resulted in granting damages to Taco Cabana. Additionally, while calculating damages the court held that Two Pesos had intentionally and deliberately infringed Taco Cabana's trade dress.
In Qualitex v Jacobson Products, 514 U.S. 159 (1995) court discussed trade dress protection in a different way. Qualitex's cleaning pads sold to dry cleaning establishments many years were green-gold in color. Jacobson Products started to sell pads of an identical color. The color was already registered by Qualitex as their trademark and they sued against Jacobson for infringement.
While considering the case the court took an opinion that color alone could be registered as a trademark. Furthermore, it was noted by the court that anything that could differentiate a provider can be registered which includes shape (of a bottle), sound (chimes or music), and odor (a particular fragrance). While presuming the above view the Court observed that color was nothing other than a distinguishing factor of a product and there was no reason to exclude color from that purview. To register color it must be distinctive and non-functional. As there is nothing essentially distinct about color, secondary meaning is a requisite to build up distinguishing element based on the aspect of color.
In order to make a color registrable it must be non-functional. If it has a function, inclusive of aesthetic function it will not be registrable. An example quoted by the Court was that of the competitors of John Deere farm equipment allowing painting their equipment green in spite of John Deere's trademark because farmers want their equipment to match. In addition the court enunciated a list with regard to the trademarks that stands above the trade dress protection. Those are:
1. § 1124 (ability to block importation of confusingly similar goods).
2. § 1072 (constructive notice of ownership).
3. § 1065 (incontestable status)
4. § 1057(b) (prima facie evidence of validity and ownership. 
The decision was reviewed by the Supreme Court of United States in Wal-Mart Stores v Samara Bros., Inc. (99-150) 529 U.S. 205 (2000). The Court decided on the circumstances under which a product’s design can be distinctive, and conditions under which it is entitled for protection where an action for infringement of unregistered trade dress under §43(a) of the Trademark Act of 1946 (Lanham Act) take place. Court held that product design, like color, is not inherently distinctive.
The Lanham Act provides for the registration of trademarks, which it defines in §45 to include:
“any word, name, symbol, or device, or any combination thereof [used or intended to be used] to identify and distinguish [a producer’s] goods … from those manufactured or sold by others and to indicate the source of the goods … .” 15 U.S.C. § 1127.
Registration of a mark under §2 of the Act, 15 U.S.C. § 1052 enables the owner to sue an infringer under §32, 15 U.S.C. § 1114; it also entitles the owner to a presumption that its mark is valid, see §7(b), 15 U.S.C. § 1057(b), and ordinarily renders the registered mark incontestable after five years of continuous use, see §15, 15 U.S.C. § 1065.
In addition to protecting registered marks, the Lanham Act, in §43(a), gives a producer a cause of action for the use by any person of “any word, term, name, symbol, or device, or any combination thereof . . . which … is likely to cause confusion . . . as to the origin, sponsorship, or approval of his or her goods . …” 15 U.S.C. § 1125(a). 
The Supreme Court held that "the breadth of the definition of marks registrable under §2, and of the confusion-producing elements recited as actionable by §43(a), has been held to embrace not just word marks, such as “Nike,” and symbol marks, such as Nike’s “swoosh” symbol, but also “trade dress”–a category that originally included only the packaging, or “dressing,” of a product, but in recent years has been expanded by many courts of appeals to encompass the design of a product. See, e.g., Ashley Furniture Industries, Inc. v. Sangiacomo N. A., Ltd., 187 F.3d 363 (CA4 1999) (bedroom furniture); Knitwaves, Inc. v. Lollytogs, Ltd., 71 F.3d 996 (CA2 1995) (sweaters); Stuart Hall Co., Inc. v. Ampad Corp., 51 F.3d 780 (CA8 1995)." 
Distinctiveness is the most important aspect of the trade dress protection. It can be either acquired or inherent. It is pertinent to have distinctiveness of trade dress in claiming a "secondary meaning” where it is can be associated with not more than one specific brand. A design to be inherently distinctive should be unusual in shape, color etc when introduced in the market that is essentially distinct from others. Whereas, acquired distinctiveness is something that is acquired by a design through marketing, advertising, promotions etc. It is a "look" that consumers associate with a particular product's brand identity. Demonstration of such association by a consumer survey or other means can provide the "look" a secondary meaning. 
It can be concluded from the above discussions that while implementing trademark and related rights such as trade dress one must constantly be aware of the necessity to trade successfully and to maintain proof of ones marketing. By doing so one may acquire secondary meaning, which is the key aspect of trade dress protection. The more distinctive is the selection of mark and packaging design is, the better will be ones chances to claim protection to trade dress.