Proficient reading requires the ability to analyze words for various properties, including pronunciation, meaning, and syntactical function. However, most instruction in word analysis is limited to phonics instruction provided in the early elementary grades. For older students, whose words largely center units of meaning, or morphemes, early phonics instruction does not provide the multifaceted knowledge of word properties these older students need to manipulate the complex words of their curricula. Therefore, this study examined the effects of direct morphological analysis instruction focusing on Latin roots on middle school students' ability to orally decode and construct meaning for morphologically complex words. Working with 63 sixth graders, the researcher provided direct morphological instruction in prominent Latin roots and morphological analysis to a treatment group of 42 students and robust vocabulary instruction focusing on words with shared Latin roots to a comparison group of 21 students. Instruction occurred over a period of 29 sessions of 15 to 25 minutes each. Prior to the first cycle of instruction and immediately following the final cycle of instruction, all students were administered assessments of oral decoding and of morphological analysis for the construction of meaning. The results from the assessment of morphological analysis indicated that both treatment instruction and comparison instruction increased students' ability to construct meaning from morphologically complex words. However, the treatment instruction had a greater impact on the students' abilities to identify morphemes, define known morphemes, and use the definitions of known morphemes to construct meaning for the whole word. The results from the oral decoding assessment showed that both the treatment and comparison instruction increased students' ability to decode morphologically complex words, with no added effect from the direct morphological instruction. The results of this study indicated the relative value of direct morphological instruction in prominent Latin roots and strategic morphemic analysis for older students. However, the results also showed a need for further research that determines an appropriate developmental sequence of morphological instruction and determines the effect of this type of morphological instruction on global comprehension abilities. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]